In-depth baby product reviews led by a Pediatrician

Cybex Sirona S Review

A high-quality seat with interesting features and better crash tests scores, but it is expensive and very heavy
Cybex Sirona S
Credit: Abriah Wofford
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Price:   $500 List | $499.95 at Amazon
Pros:  High quality, comfortable, better crash score, longer potential lifespan
Cons:  Not fans of the infant to toddler designs, expensive, heavy
Manufacturer:   Cybex
By Wendy Schmitz and the BabyGearLab Review Team  ⋅  Nov 10, 2021
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69
OVERALL
SCORE


RANKED
#8 of 18
  • Crash Test - 35% 7
  • Ease Of Install - LATCH - 20% 7
  • Ease Of Install - Belt - 15% 6
  • Ease Of Use - 15% 7
  • Comfort / Quality - 10% 9
  • Weight / Size - 5% 4

The Skinny

The Cybex Sirona S is a gadget-filled convertible car seat suitable from infancy through the beginnings of toddlerhood. This "install it once" car seat offers easy-to-use LATCH connectors and a rotating seat that allows you to set it and forget it, making it appealing to parents who hate installation. Cybex has added other safety features like a load leg, anti-rebound bar, and side-impact pop-outs to their high-quality, high-dollar seat, which may have helped it achieve better than average crash-test results. Unfortunately, this is one of the most expensive seats in the review, making it a non-starter for some on tighter budgets. It is also the heaviest option, so it isn't suitable for those needing to carry their seat or transfer it to another vehicle regularly. While this seat is nice to look at and performs above average in most metrics, it is cumbersome and expensive. With several options scoring higher with better features, the Sirona S struggled to meet the competition.

Compare to Similar Products

 
Cybex Sirona S
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Cybex Sirona S
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Price $500 List
$499.95 at Amazon
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Overall Score Sort Icon
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Star Rating
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Pros High quality, comfortable, better crash score, longer potential lifespanEasy to install and use, cozy comfort, nice qualityBest crash test results, rear-facing till 50 lbs, priceGreat crash test results, easy to use, attractive price, lighterBudget-friendly, better crash test results, narrow
Cons Not fans of the infant to toddler designs, expensive, heavyAverage crash test resultsNot the best quality, harder belt installationHarder to install using the vehicle beltThin padding, harder to install, lower quality
Bottom Line A high-quality seat with interesting features and better crash tests scores, but it is expensive and very heavyImpressive option with quality features and super easy installation parents will loveBest crash test results on a budget-friendly seat that lets little ones sit rear-facing for longerA lightweight, easy to use seat with excellent crash test result and priceInexpensive choice with impressive crash test results
Rating Categories Cybex Sirona S Britax Boulevard Cl... Graco Extend2Fit Britax Emblem Evenflo Tribute LX
Crash Test (35%)
7.0
6.0
9.0
8.1
8.0
Ease Of Install LATCH (20%)
7.0
10.0
7.0
7.0
5.0
Ease Of Install Belt (15%)
6.0
10.0
7.0
6.0
5.0
Ease Of Use (15%)
7.0
8.0
7.0
8.0
7.0
Comfort Quality (10%)
9.0
9.0
6.0
8.0
3.0
Weight Size (5%)
4.0
5.0
5.0
6.0
10.0
Specs Cybex Sirona S Britax Boulevard Cl... Graco Extend2Fit Britax Emblem Evenflo Tribute LX
Min/Max Rear Facing Passenger Weight 4 - 65 lbs 5 - 40 lbs 4 - 50 lbs 5 - 40 lbs 5 - 40 lbs
Min/Max Forward Facing Passenger Weight 22 - 65 lbs 20 - 65 lbs 22 - 64 lbs 20 - 65 lbs 22 - 40 lbs
Max Rear Facing Passenger Height 49" Child's head must be at least 1 in. below the top of the head restraint Child's head must be at least 1 in. below the top of the head restraint Child's head must be at least 1 in. below the top of the head restraint 37"
Max Forward Facing Passenger Height 65" 49" and the child's ears must be below the top of the head restraint. 49" and the child's ears must be below the top of the seat shell. 49" and the child's ears must be below the top of the head restraint. 40"
Measured Rear Facing Seat Weight 30 lbs 29.5 lbs 18.7 lbs 18.8 lbs 9.3 lbs
Measured Forward Facing Seat Weight 30 lbs 28.4 lbs 18.7 lbs 18.8 lbs 9.1 lbs
Width 19" 18" 19.6" 18.9" 17"
Recline Positions 12 7 4 Rear Facing
3 Forward Facing
1 Rear Facing
2 Forward Facing
1 Rear Facing
1 Forward Facing
Max Recline Angle 52° 51° 51° 42° 45°
Shoulder Harness Positions 9 14 10 10 4
Crotch Strap Positions 3 2 2 2 2
Built in Lock Off Yes No No Yes No
Anti-rebound Device No Yes No No No
Head Support Yes Yes No No No
Newborn Insert Yes Yes Yes Yes No
No Rethread Harness Yes Yes Yes Yes No
Onboard Manual Storage Yes Yes Yes Yes Yes
Level Indicator On Seat Ball in Tube Ball in Tube. Ball in Tube. Line on Decal Line Molded onto Shell
Foam Type EPP EPP EPS EPP EPS
Seat Lifespan 10 yrs 10 yrs 7 yrs 7 6 yrs
Warranty 3 Years 1 Year 1 Year 1 Year 90 Days

Our Analysis and Test Results

German-born Cybex is a part of Goodbaby International Holdings Ltd. They focus on products with an eye for functionality and safety in their designs. They offer a variety of strollers, carriers, and car seats.

Performance Comparison



This Cybex has pop-out side-impact accessories that the manufacturer...
This Cybex has pop-out side-impact accessories that the manufacturer claims increase crash test performance.
Credit: Abriah Wofford

Crash Test


The Sirona S performed better than average for crash test results in our tests. It offered impressive performance for the Head sensor result (HIC) score, but less impressive results for the chest clip compared to the competition. Like all other seats for sale in the US, it has a basic level of protection and met the federal standards for car seat safety.

The chest sensor result on the Sirona S was 50 where 60 is the maximum allowable result. A lower result is better. The lowest, and therefore best, result in the group is 33 for the Clek Foonf (see below).

The chart above shows a comparison between the Sirona S and the...
The chart above shows a comparison between the Sirona S and the top-scoring seat for chest clip, the Clek Foonf.
Credit: MGA, BabyGearLab Staff
The chart above shows a comparison between the HIC sensor results on...
The chart above shows a comparison between the HIC sensor results on the Sirona S and the best performing seat for HIC, the Britax Allgiance.
Credit: MGA, BabyGearLab Staff

The Sirona S head sensor (HIC) result was 231 where 1000 is the maximum, making it one of the best in the group and far below the allowable max. The Britax Allegiance earned the best sense result in this metric with a result of 186. See the comparison chart above.

The load leg on the Sirona S has a color change indicator when the...
The load leg on the Sirona S has a color-changing indicator when it...

This Cybex Sirona also features side-impact protection, an anti-rebound feature, and a load leg to help absorb impact forces during a crash. how well these features work is anyone's guess and in our crash testing across seat types we've seen results that show the load leg to be beneficial for some seats and not for others. We love safety at BabyGearLab, but it is challenging to determine the efficacy of manufacturer claims or test results without more information on how they were derived.

Installation of the Sirona S is easier when using the LATCH anchors...
Installation of the Sirona S is easier when using the LATCH anchors, but both utilize the belt lock-off mechanism.
Credit: Abriah Wofford

Ease of Install - LATCH


The Sirona S LATCH installation is different than most of the competition as it still requires the use of the belt lock-off system that works with the vehicle belt installation. Most seats do not utilize the belt lock-off for LATCH anchor installation.

The LATCH connectors on the Sirona have a push button and a pull...
The belt pathway is accessible under a compartment door. It is easy...

The LATCHes themselves are different than any other we've seen, with a large push button and strange red pull strap. They aren't hard to use, but we aren't convinced the changes make them better than the average LATCH. However, you only need to install this seat once, theoretically, since the seat itself rotates on the base when you're ready to move it to a forward-facing position, so perhaps the strangeness of the LATCH anchors isn't a huge deal.

The belt pathway on the Sirona S travels through the base and the...
The Sirona S has a belt tensioner system under a hidden compartment...

Ease of Install - Belt


The Sirona belt installation isn't as simple to install as the LATCH method, which isn't shocking. It earned a slightly lower score for this type of installation. The Cybex has a removable cover on the belt path, which Is helpful because when it is off, the car seat locks into a position that keeps it out of the way while you thread the belt. The seat rotates out of the way to access the belt path and this is better than those that require threading behind the seat padding.

Using the belt lock-off/tensioner on the Sirona S isn't difficult...
The Sirona S belt tensioner is a two-step process that still...

The belt lock-off compartment is easy to open and the belt is easy to get into place. However, we still had to tighten the belt significantly to feel like it was secure before pushing the belt-tensioner into place. So while it is nice to have a belt lock-off, and we believe they are the key to secure belt installation, this one didn't work as well at keeping the belt tight as some of the competition.

The angle of the Sirona S can be adjusted after seat installation.
The level on the Sirona S is easy to use and works well.

Once installed, the Sirona angle is adjustable (above left) after installation which is rare in convertible seats. It sports a metal ball level indicator on the base that works well (above right).

The Sirona S would be easier to use if it only had fewer gadgets and...
The Sirona S would be easier to use if it only had fewer gadgets and things were smoothie in their operation.
Credit: Abriah Wofford

Ease of Use


The Cybex is easy to use but it is sort of gadget-filled which impacted its overall ease of use score making it slightly lower than it might otherwise have been.

The headrest assembly on the Sirona S has a pull handle that...
The headrest assembly on the Sirona S has a pull handle that requires an almost double pull to work properly.
Credit: Abriah Wofford

Harness


The Sirona harness is a non-rethread height adjustment that moves with the headrest and can be done with a baby in the seat. There are 9 shoulder strap positions and 3 crotch strap positions. The assembly moves fairly smoothly, but the handle is somewhat hidden and you have to pull up before you can move the headrest, which ameks it marginally more difficult than some of the competition.

The chest clip on the Sirona S is more challenging to use than most...
The chest clip on the Sirona S is more challenging to use than most of the competition because the button needs to be pressed to open and close the clip.
Credit: Abriah Wofford

The buckle is stiff but pops open with a spring action when pressed making the stiffness more tolerable. It is the chest clip that is the real hassle for this entire operation. The chest clip has a small button on the front that needs to be pressed when you put the two sides together and when you want to take it off. It makes the whole process somewhat of a chore and we can see this be annoying with a squirmy toddler in the seat. The pull strap to tighten the harness is extra long and works well. The release button is extra deep, but is easy to press and operates smoothly.

The LATCH connectors on the Sirona S tuck in the bottom of the seat...
The user manual for the Sirona S has a home in a compartment on the...

LATCH Storage


The LATCH connectors attach under the seat (above left) and while this keeps them out of the way, it doesn't look as sleek as some of the competition. The user manual tucks in a pocket on the back of the seat (above right).

Cover


The cover for this Cybex is removable and you can wash it in the machine on cold. It is easy to remove and replace after air drying, but some kind of utensil might help you tuck the edges back in. Given babies' ability to create a huge mess, this is a big deal and not found in all of the seats we tested.

The Sirona S earned its top marks for quality and comfort with...
The Sirona S earned its top marks for quality and comfort with significant padding and skin-friendly fabric.
Credit: Abriah Wofford

Comfort/Quality


The Sirona S earned one of the top scores for comfort and quality in this review. This seat is also one of the most expensive options as well.

This Cybex uses EPP foam for impact absorption. This type of foam is...
This Cybex uses EPP foam for impact absorption. This type of foam is less brittle and marginally more eco-friendly.
Credit: Abriah Wofford

The Cybex padding is better than most of the competition and it offers firm supportive comfort. The fabric feels softer and more friendly than the other Cybex convertible seat we reviewed. It has a very dense weave that should wear well over time and helps make it easier to wipe up messes. The foam sits well on the frame and the fabric looks custom fit without frumpiness. The shell is enclosed making it easier to keep clean and gives it an overall sleek and finished look. The bottom of the seat is not smooth, but the protrusions are rounded and this should help protect vehicle seats.

Because the base and the seat are one component on the Sirona S, it...
Because the base and the seat are one component on the Sirona S, it is very heavy and we suspect prohibitively so for most parents who may need to carry it for any distance or time.
Credit: Abriah Wofford

Weight


This Cybex weighs 30 lbs, in either forward or rear-facing configuration. This makes it one of the heftiest options in the group and we would recommend it to anyone who will need to move it from car to car frequently, or need to carry it any distance.

This Cybex is 19 inches wide at its widest point. This makes it fairly large but not in contention for the widest seat in the review. This width is only a concern if you hope to fit more than two car seats across one row or two-seat and an adult passenger between them. If you hope to use more than 2, then it isn't likely your best choice.

Manufacturer Video



Wendy Schmitz and the BabyGearLab Review Team

Honest, objective reviews. Led by a Pediatrician.

BabyGearLab was founded by a Pediatrician Mom with a mission to provide a reliable, independent, source of information to new parents. Our experts have tested thousands of baby and kids products to share key performance, health, and safety findings. We spend tens of thousands of dollars crash testing car seats to inform our ratings. And, we combine our review work with gobs of expert parenting advice. To assure complete independence, we buy all the products we test ourselves. No sponsored content. No ads. Just real, honest, side-by-side testing by people who care.

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