Nuna Revv vs Cybex Sirona S Comparison

Both the Nuna Revv and Cybex Sirona S swivel, making easier the task of loading and unloading kids. But the Nuna Revv costs over $100, and this Nuna Revv vs Cybex Sirona S comparison makes it easier to decide whether the price difference is justified.

In case you’re interested, I recently wrote a comparison post on Nuna Revv vs Evenflo 360 Gold.

The Nuna Revv may have a more solid feel and build and plusher padding and looks a tad nicer. But I still insist that the Cybex Sirona S is the brainier buy. Learn why in the description below:

Also Read: Evenflo Revolve 360 vs Cybex Sirona S

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CYBEX Sirona S Rotating Convertible Car Seat
Ideal for rear-facing only
Nuna Revv Convertible Swivel Car Seat
Product Name
Product Name
CYBEX Sirona S Rotating Convertible Car Seat
Nuna Revv Convertible Swivel Car Seat
Features & Specs
Features & Specs
Side-impact protection, adjustable headrest, adjustable crotch buckle, 5-point harness, bubble recline indicator, top tether, 360˚, usable as a booster car seat
Side-impact protection, anti-rebound bar, recline level indicator, thickly padded & washable padding, removable infant support wedge,
Rear-facing weight limits
Rear-facing weight limits
Forward-facing weight limits
Forward-facing weight limits
Rear-facing height limits
Rear-facing height limits
Forward-facing height limits
Forward-facing height limits
Infant insert
Infant insert
Included & washable
wool head&body insert, non-washable
Unique features
Unique features
Safety alert-sending SensorSafe, Tether for forward-facing only, onetime install, extended rear-facing, adjustable crotch buckle, dishwasher-safe cupholder, bead recline indicator, & load leg
A stylish look, plush seat pads, one-time install, extended rear-facing, an extremely solid build, spins flawlessly, tether used rear-facing&forward-facing, no-rethread harness, adjustable crotch, bubble-free recline indicator, lap portion of seatbelt used to install
Little things to know
Little things to know
Top tether useless forward-facing, load leg can bend out awkwardly if backseat is too steep going backward
top tether overlaps the shoulder portion of the vehicle’s seatbelt (Nuna doesn’t say this could be a problem though),Insanely low max harness height (14″), ridiculously low forward-facing weight and height limits, insert should be spot cleaned
Booster Mode? No
Booster Mode? No

Swivel car seats have become a feature parents are willing to pay extra for. That’s because a good rotating car seat makes strapping baby in as well as unloading them incredibly easy.

And if you have a rather chunky child or have a weak back and generally have trouble bending over to lift things, you’ll greatly appreciate the tons of convenience a turning car seat brings to the parenting table.

The seat turns towards the side so that baby faces the vehicle’s door, which makes handling them super easy. With a car seat like this, your baby won’t get head hits when you’re getting them out of space-poor backseats.

But all new fancy features tend to drive item cost up, and it’s no different with car seats that swivel. Be ready to part with at least $320 for the car seat for the Evenflo 360 Gold, which I consider to be the best convertible swivel car seat on the market today.

But Nothing is 100% Perfect, Including Swivel Car Seats

Car seat designers and engineers are really smart people who do everything their capability and creativity enables them to do, but pretty much every car seat has a con or two.

Swivel car seats are heavy and bulky, which makes moving them between cars a strenuous task. The base is typically permanently attached to the seat shell, and even for the Evenflo 360 Gold which boasts a removable shell, you won’t find extra bases to install in other cars.

Also, you can’t use swivel car seats with strollers because the base doesn’t detach from the car seat’s shell. And obviously, you can’t take out the seat itself and use it as a portable carrier as you would with an infant car seat.

However, the Orbit G5 Car Seat is an exception because it lets you remove the infant car seat and carry baby around when outside of the vehicle. Actually, this isn’t a convertible car seat.

There’s one more thing: most car seats that revolve around the base tend to not be aircraft travel-friendly because they’re not FAA-approved. If you want an FAA-approved car seat that swivels, the Orbit G5 Travel System it is.

Nuna Revv Convertible Rotating Car Seat Specs and Features

You can the Nuna Revv 360 Review here. And if you’re interested to read nuna revv reviews, go to the brand’s website and read what those who bought the car seat say about it.


Rear-facing weight limits: 5-40lbs

Rear-facing height limit: 43 inches

Forward-facing height range: 25-40 inches

Forward-facing height limit: 43 inches

Forward-facing age: 2+ years

Lower anchor weight limit (rear-facing): 30lbs

Lower anchor weight limit (forward-facing): 30lbs

FAA-approved? No


Swivels 360˚

Top tether for rear-facing & forward-facing

No rethread harness

Strong, durable steel frame (Steel Strength Technology)

Multi-position (10) headrest

Recline positions: 10 positions, 5 rear-facing & 5 forward-facing

Energy-absorbing EPP foam

Two removable cupholders (manual is silent on whether if they’re dishwasher-safe, but Nuna says they are)

Magnetic buckle holders: for keeping harness straps out of the way when buckling in baby

Anti-rebound bar: Yes, an integrated anti-rebound bar that doubles up as a carry handle

Load leg: No

Booster seat mode? No

Side-impact protection? Yes, Aeroflex Side Impact Protection System

Fabric & padding quality: Plush, highly breathable, & washable. Run load through a gentle cycle with cold water & a mild detergent

True Tension Door for tightening the seatbelt or lower anchors

Made of fire-retardant free materials, which means no added chemicals that could harm your child

GREENGUARD GOLD-certified: Yes. This internationally recognized certification indicates that the car seat entirely meets the emissions requirements for at least 360 chemicals & Volatile Organic Compounds (VOCs).

You don’t want your little one inhaling any kind of chemical compounds, even if you have the best car air purifier for fumes.

Critical Numbers of the Nuna Revv Rotating Car Seat

Dimensions: 21.5-22.5″ L x 16″ (w/o cupholders)-22.5″ (w/ cupholders on)  W x 22.5-29.5″H (Length and height varies depending on headrest and recline positions)

Weight: 32.7lbs

Highest harness height: 14 inches

Lowest harness height: 6.5 inches (with insert) & 8 inches without insert

Width: 22.5 inches at the widest point (with cupholders installed) & 16 inches with the cupholders removed

Cybex Sirona S 360 Specs and Features

Also Read: Cybex Sirona S Review


  • Rotation: 360˚
  • Longevity: 10 years from date it was manufactured
  • Maximum weight limit (rear-facing): 4-50lbs
  • Maximum height limit (rear-facing):17″-49″
  • Lower anchor weight limit rear-facing: 30lbs
  • Forward-facing weight limits:22lbs-65lbs
  • Forward-facing height limits: 28″-49″
  • Lower anchor weight limit (forward-facing): 35lbs
  • FAA-approved? Aircraft-approved in Canada but NOT in the United States

Car Seat Measurements

  • Dimensions: 25.3″ L X 20″ W X 25.5″H
  • Weight:31lbs
  • Width: 21″ at the widest point
  • Highest harness height: 16.5″
  • Lowest harness height: 7″ with the insert & 8″ without insert
  • Seat depth: 13″
  • Crotch buckle positions: 3 positions at 5″, 6″ &7″


  • Optional infant insert: It’s removable and washable
  • Linear Side Impact Protection (LSP): Padding extends from the sides, and it increases protection against side impacts
  • Chest clip equipped with SensorSafe for timely safety alerts.
  • Adjustable load leg for reducing rotation and movement to increase safety for rear-facing &  forward-facing use
  • Car seat has a panel with protective properties; it serves as anti-rebound mechanism rear-facing
  • Headrest adjusts and there’s no re-threading the 5-point harness afterward
  • Car seat revolves on a base that stays in the backseat
  • Seat lock feature: Lets you know when the seat docks into place for safe use while vehicle is in motion
  • Colors sold in: Manhattan Gray, indigo Blue, and Premium Black (price you pay depends on the color you choose)
  • Reclines forward-facing & rear-facing

Now that the specs and features are out of the way, let’s dive deep and see what our comparison of the Cybex Sirona S vs Nuna Revv Rotating Car Seat surfaces.

Cybex Sirona S vs Nuna Revv Rotating Car Seat: Which is the Better Buy?

To make this an easy-to-follow discussion, I’ve partitioned my analysis into a bunch of focused sections. Each portion takes a closer look at a specific comparison aspect such as weight limits, harness height, features, construction quality, ease of installation, and so on. So, let’s get going.

Car Seat Weight: Who’s Heavier and Does It Matter?

When it comes to convertible rotating car seats that stay in the car for the most part, weight isn’t such a big deal. A lighter swivel car seat could be better than a heavier one if you envision yourself using it in multiple cars at different times though.

But most parents prefer to install heavy bulky convertible car seats in one car and don’t move them much at all.

The Cybex Sirona S weights in at 30.4 pounds while the Nuna Revv Convertible car seat weights in at 32.7 pounds. Nuna Revv wins here, but not by a huge margin, and the weight difference doesn’t make much of a difference in the end. I bet you won’t notice any difference when carrying one car seat or the other between cars.

Here’s a little piece of advice that’ll save your back tons of trouble: once you install either car seat in the backseat of your car, let it stay there. Unless you really need to transfer it to a different vehicle, don’t uninstall either option.

Nuna Revv vs Cybex Sirona S: Weight and Height Limits Rear-facing

I’ll start with the weight limits rear-facing and then proceed to the height limits.

Weight Limit Rear-facing

Experts everywhere are in agreement that the safest way to carry a child around is in the rear-facing position. A decent stack of scientific studies consistently finds that it’s best for people who travel with kids to rear-face them for as long as possible.

In fact, you should start rear-facing baby right from the day you’re discharged from the hospital according to the American Academy of Pediatrics.

The AAP constantly reminds parents and caregivers about this truth: rear-facing in the backseat (preferably in the middle) is the safest place to ride in for newborns and toddlers up to 2 years.

Also, the National Highway Traffic Safety Administration holds this position as do pediatricians who also happen to be trained child passenger safety technicians (CPSTs).

Now here’s the thing: Both the Nuna Revv and Cybex Sirona S make it easy to carry baby rear-facing. But while the Nuna Revv’s limit stretches from 5-40lbs, its competitor’s weight range starts at 4lbs and extends all the way to 50 pounds. 

Yes, you heard me right: it’s 50lbs maximum rear-facing limit with the Sirona S vs. 40lbs with the Nuna Revv Rotating Car Seat.

This means you can do extended rear-facing with either choice all other things being equal. But are all other things equal? No, and I’ll tell you why the Nuna Revv is the less attractive option shortly.

Height Limits Rear-facing

The height limits is where differences between the Nuna Revv and Cybex Sirona S really begin to emerge. While the former offers a maximum height range of 43 inches, the latter offers an upper limit of 40 inches.

So does this mean that the Nuna Revv is the better choice when it comes to extended rear-facing? Not really. Let me explain: the Nuna Revv Convertible Car Seat has a maximum harness height of just 14 inches.

Now 14″ may not mean much at all to you if you don’t know the maximum harness height competing swivel car seats offer.

Take the upper harness height for the Evenflo Gold 360, for example. It is 19″ for this car seat, which I believe is the best swivel car seat ever made. If you have taller toddler, this is the option to pick.  Sure, this guy has a flaw or two, but it’s the best buy for the money. Find other car seats that rotate here.

As for the Cybex Sirona S, the maximum harness slot height is 16.5″, a full 2.5″ higher than the highest seating harness slot on the Nuna Revv. This means that there’s a FAT chance your baby will outgrow the Nuna Revv swivel car seat way sooner than you imagine.

Forward-facing Weight and Height Limits for Cybex Sirona S vs Nuna Revv

For the Nuna Revv, the forward-facing height limit is 43″, same as the limit rear-facing. I couldn’t wrap my head around this little fact: 43″ rear-facing and 43″ forward-facing.

As if this wasn’t enough, Nuna offers a maximum weight limit of 40 pounds forward-facing, which is exactly the same number you get in the rear-facing position. Again, I can’t understand this for the life of me.

I mean, kids are always growing and adding weight, but Nuna seems to be completely unaware of this fact. For a $600ish swivel car seat, I expected an all-in-one convertible car seat with a booster seating mode. I expected a forever option, something you could use from birth until the child was ready for the booster car seat.

But I was disappointed. Because the Nuna Revv forward-faces up to just 43″ compared to 49″ for the Cybex Sirona S. Add in the little fact of an extremely low maximum harness height limit of 14″, and you’ll clearly see why the Nuna Revv may not be an appealing choice for most families.

Most Kids Don’t Use the Forward-facing Mode on the Nuna Revv!

Yes, that’s 100% true. The Nuna Revv is never a forever convertible car seat. While really tiny tots could use the car seat forward-facing for some time, most kids outgrow pretty soon.

Many parents soon realize that the Nuna Revv is NOT an all-in-one turning car seat, and that they need to set aside some extra money for another convertible car seat or forward-facing car seat pre-booster age.

If you hate the idea of spending more $$ in the future to achieve the same goal you’d have reached with a real all-in-one option such as the Evenflo 360, definitely skip the Nuna Revv. Because you’ll regret the purchase sooner than I predict you will!

Installing the Nuna Revv vs Installing the Cybex Sirona S

Installing each of these car seats via the seatbelt isn’t hard, but take care when handling the Sirona S. Why? Because the belt path isn’t as wide as it probably should be, and you’ll likely get your hand scraped while seatbelt or lower anchor routing.

For the Sirona S, the lower anchor weight limit rear-facing is 30lbs while for the Nuna Revv it is 30lbs. Clearly no winner here.

Forward-facing, the limit is 35lbs for the Cybex while it is 30lbs for the Nuna Revv. Evidently, the Sirona S registers a higher limit forward-facing, but of what use is a higher number when you’ll have to uninstall the seat and reinstall in the near future?

One advantage of a car seat that swivels 360 degrees as these two guys do is that you can get away with a onetime install.

If you use the seatbelt to install either the Cybex Sirona S or Nuana Revv, you can install it once and use it in that position until your baby outgrows the seat. Or until you need to install either seat in a different vehicle, something I discourage unless you like carrying heavy things and doing tricky car seat installs.

Installing Via Seatbelt is Challenging for Both Nuna Revv & Sirona S

I wish I could say that installing the Sirona S or the Nuna Revv is easy, but I’d be lying. In truth, installing the Sirona S with the seatbelt can be quite the challenge, and setting the Nuna Revv up turns out to be an even bigger challenge.

To learn how to install the Nuna Revv rotating car seat, read this easy-to-follow installation guide created by the good people over at Car Seats for the Littles. Or watch this video. I judged the parent-published video content to be more helpful than the videos the manufacturer put out.

Here are how-to-install-Cybex-Sirona-S videos and here’s a written resource that’ll make installing the car seat via the lower anchors or seatbelt a tad easier.

I’m sure you’ve watched the notoriously short videos created by the marketing folks at car seat and stroller brands and seen how effortlessly they fold down strollers and install car seats. But try to do what they do in real-life situations often proves harder than the videos suggest!

Remember: if you want a onetime installation of either car seat, make sure to use the vehicle’s seatbelt and NOT the lower anchors.

Headrest, Harness, Harness Cover, and Crotch Buckle

The headrest on both seats pull out and upward to accommodate the increasing head height of a growing kid. But don’t expect much from the Nuna Revv since its max harness height is extremely low. To effect a height adjust on either option, simply grab the handle on the top and pull up.

The harness is no-rethread in both cases, which means you won’t need to go back and re-work the harness straps after adjusting the headrest. And as you might already expect, it’s a highly protective 5-point harness on both seats, and there’s a decent-quality harness cover whichever deal you pick.

The crotch buckle allows for adjustments to create a much better fit, but be ready to put in a little more work when working the buckle on the Nuna Revv.

You’ll find it necessary to remove the padding to access the slots and adjust the crotch buckle, and this can be a bit of a challenge. But I like that the crotch buckle does stay attached to the car seat.

On the Nuna Revv, the crotch buckle boasts a plush cover, which is nice. But this cover can slowly slide out of place when moving the car seat. Make sure to slide back into place the tiny tab that holds the cover to the seat to keep it from straying.

Seat Build, Seat Padding, and Infant Insert

A durable steel frame supports the shell and everything else for both seats, and they feel like a really solid build. It sure does feel like the tiny passenger would get reliable protection in a crash, but the Nuna Revv looks and feels somewhat beefier and sturdier.

Also, both offer good side-impact protection for increased safety in the event of side impacts.

Both seats have nice padding, but it’s noticeably thicker and seemingly comfier on the Revv. And in both cases, you can remove the seat covers and toss them in the washing machine.

I like that both choices come with an optional infant head and body insert. The insert isn’t foldable in both cases (as it is in Evenflo 360 Gold).

But I did find that removing it from the Nuna Revv when strapping in a bigger tot may result in a somewhat better fit. Only via trial and error can you know for sure whether the fit is better with or without the insert. And when baby reaches 11lbs, you should take off the infant wedge.

You can wash the infant wedge of the Cybex Sirona S, but the one on the Nuna Revv shouldn’t be washed according to the manufacturer’s manual.

Top Tether and Its Ease of Use

There’s a top tether on bother products to hold the seat in place during a collision, preventing it from flying forward with baby in the case of the Sirona S or forward&backward in the case of the Nuna Revv.

For the Nuna Revv, the top tether is used forward-facing and rear-facing while it’s only used forward-facing on the Cybex Sirona S.

On both options, the tether attaches to the shell instead of to the base, and this causes problems. For Sirona S, the top tether obstructs the rotational function as to render it completely useless forward-facing, but it’s pain-free for rear-facing use.

As for the Nuna Revv, the instructions manual says to route the top tether over the anti-rebound bar, which also functions as a carry handle. But the company’s technical writer seemed to have forgotten to tell users where the shoulder portion of the seatbelt should be placed.

Consequently, the shoulder section of the seatbelt stays at a certain angle and ends up getting in the way of the top tether, which comes out of the base. See this photo of the Nuna Revv installed in a vehicle to understand what I mean.

Having an anti-rebound bar on the Nuna Revv is in a sense a blessing and a curse. I checked Nuna’s website, and the pictures show that the shoulder portion should crisscross the top tether the way it does in the link above. But they should have indicated in the installations instructions whether the overlap is OK.

Seatlock and Recline Level Indicators

Both have seat lock indicators that change color from green to read and vice versa to indicate current status. When you dock the seat into position, the indicator displays in green and stays red when not locked.

This little feature increases safety because you won’t want to take off until the seat is well and truly in the locked position.

Also, both have recline level indicators. But there’s a difference: while the recline indicator on the Sirona S is a bead-based affair that can be a little tricky to use, the indicator on the Nuna Revv has numbers 1-5 for rear-facing and 1-5 for forward-facing mode. This bubble-free indicator tends to be easier to easier to use when adjusting car seat recline.

Nuna Revv recline indicator
Nuna Revv recline indicator

Both Have Optional Dishwasher Cupholders

It’s nice that both car seats have optional cupholders. But I found that the cupholder on the Cybex Sirona S could be improved in terms of overall quality. It feels like flimsy plastic, and most kids won’t need to exert much force to knock it out of place.

I like the quality of the cupholders on the Nuna Revv better. However, if you have a really fussy kid, they could end up spilling stuff especially if the cup is rather tall. Because the holders aren’t as deep as they could be.

Anti-rebound Bar/Load Leg and SensorSafe for Safety Alerts

While the Cybex Sirona S has a protection-increasing load leg, the Nuna Revv relies on the carry handle to do the job. This integrated handle serves as an anti-rebound bar that reduces movement during a crash. Both technologies aim to achieve the same aim, and this resource explains the difference.

load leg cybex sirona s

Some believe load legs protect better than anti-rebound bars, see this discussion, but very few US car seats have a load leg. The Sirona S is one of the few ones with this safety feature on top of its chest-integrated SensorSafe that sends critical alerts about baby.

The Nuna Revv lacks the SensorSafe, but this shouldn’t be a big deal unless you’re extremely forgetful and can leave baby in the backseat. If the backseat heats up, the SensorSafe feature alerts you by sending a notification via smartphone or car receiver.

But you may have to change the battery. Because in some cases, the battery that comes with seat is fried or something and fails to work.

More about the load leg on Sirona: Some reviewers had trouble getting the load leg to bend out at 90 degrees. Instead, the leg came out at a different angle raising questions as to its protective ability in a dire situation.

If your backseat slopes backward too much, you’ll likely experience this issue. Owners of flatter backseats complained less though.

Is the Price Difference Reasonable?

At time of writing, the Nuna Revv cost roughly $600 while the Cybex Sirona S costs about $450-$550 depending on who you get it from and the color chosen. But is the $50-$150 price difference justifiable in any sense?

No, I don’t believe there’s any way anyone could justify such a significant price difference. I mean, you’re definitely going to part with more money for another convertible car seat or forward-facing-only seat.

In the end, you’ll have sent way above what you’d have spent had you purchased the Sirona S right from the get-go.

I say get the Sirona S and carry your kiddo until they’re grown enough for you to buckle them in a booster seat. Not only will you save money and time this way, but it also means fewer installations overall.

Nuna Revv vs Cybex Sirona S Comparison: Who Won?

Both are nice-looking convertible car seats with a stylish modern look and feel. Also, both have plush padding and most kids fall asleep in them pretty fast. Most importantly, both are decent convertible car seats that swivel.

But there’s one thing that sets these two options apart: longevity. You may not be able to use the Nuna Revv past the rear-facing phase due to its terribly low harness height as well as really low forward-facing height and weight limits. In fact, be ready to buy a second convertible car seat if you choose the Nuna Revv over the Cybex Sirona S!

Finally, the Nuna Revv costs significantly more than the Sirona S, which I found a little baffling given its abysmal stats as far as weight and height limits.

Both aren’t FAA-approved, which you shouldn’t find troubling since you won’t want to travel with super heavy car seats anyway.

Given all these considerations, I hereby hand the medal to the Cybex Sirona S. I also declare the Nuna Revv 360-rotating car seat as one of the finest convertible car seats for rear-facing seating.

Author: Joe Waweru

As a medical professional practicing in the United States, Joe Waweru medically reviews every piece of relevant content at, but nothing he says here should be construed as medical advice of any kind.

Joe Waweru

As a medical professional practicing in the United States, Joe Waweru medically reviews every piece of relevant content at, but nothing he says here should be construed as medical advice of any kind. He's also an entrepreneur of some sort, but he prefers to keep this under wraps. <a href="Visit Joe's Facebook Profile here

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