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Hands-on Gear Review
Britax Marathon ReviewPrice: $290.00 List | $268.99 at Amazon - 7% off
Pros: Good crash test results, easy installation, nice features
Cons: Hidden belt pathway that is harder to use
Bottom line: Everything you're looking for with ease of installation, ease of use, and quality construction
The Britax Marathon (model G4.1) is the second highest ranking seat in our Convertible Car Seat Review. It managed a score of 82 out of 100 and had higher than average scores in every metric including crash test scores and ease of installation and use. This seat is a soft, comfortable seat that is easy for parents to install and use. It is hard to find anything wrong with this lovely product that also has the easiest to use non-rethread harness height adjustment and ten height positions for maximum adjustability and best fit for children of all sizes. This seat shines in comparison to the competition and is a standout no matter what may be important to you.
RELATED REVIEW: The Best Convertible Car Seats of 2018
Our Analysis and Hands-on Test Results
We tested the Britax Marathon model G4.1, which first became available in Oct 2014 when it replaced the G4. The Marathon features what the manufacturer calls "SafeCell" impact protection system with what it claims are safeguards for side impact protection with an impact absorbing base that compresses to reduce rough force. It has a steel frame and a deep foam lined shell with patented staged release stitches that should slow the seats forward motion during a crash. The seat offers what they claim is an impact absorbing harness pad to reduce forward movement, and a V tether that should minimizes seat rotation with a unique 2 strap design. The seat works for rear facing children from 5-40 pounds and up to 49 inches, and forward facing for children 20-65 pounds and up to 49 inches. The Marathon has a 3 position recline for angle adjustment, with a non-rethread harness that can adjust to 10 different positions. It has a removable body pillow and an easy to remove washable cover. It is engineered, tested, and made in the USA with global components.
This chart provides a comparison of the overall scores for all of the convertible seats we tested in this review. The Britax Marathon is shown in blue.
The sections below provide detailed information on how the Marathon performed during testing for each metric. The metric scores were used to determine the overall score with an emphasis on crash test results and ease of installation.
The Britax Marathon earned the highest overall crash test score in the review. While it did not have the lowest recorded G-force data for either the chest or head sensor taken from the crash test dummy, it did have the lowest scores across the two. This seat, like all others in this review and for sale in the United States, meet or exceed the Federal safety guidelines outlined in FMVSS 213.
Therefore, each seat is considered to be safe. Our testing is designed to the same specifications as those used by the National Highway Traffic Safety Administration (NHTSA), so we could provide a true side-by-side comparison for each seat. Some seats, including the Marathon, have test results that indicate an additional margin of protection with G-force recordings that are significantly lower than the maximum allowable amount, and lower than much of the competition.
The charts included here show the data collected during testing from the sensors in the test dummy for the Marathon (shown in black). Also, the charts include the crash test data results for the seats that have the lowest recorded amount of G forces during testing for comparison purposes (shown in green).
The Evenflo Tribute LX sensor recorded the lowest amount of G forces in the head sensor during crash testing than any of the other products in this review. The Clek Foonf has the lowest amount of G forces recorded for the chest sensor for the products in this review. The Marathon has the second lowest head G forces and the third lowest chest G forces for the group.
Ease of Install - LATCH
The Marathon earned a 9 of 10 for ease of installation using the LATCH system. The Marathon tied with the Roundabout with essentially the identical LATCH system, and the Chicco NextFit that sports what the manufacturer calls "SuperCinch".
The Clek Foonf, Britax Boulevard ClickTight ARB, and the Britax Advocate ClickTight earned the high score with a perfect 10.
Installing this seat using LATCH is a simple procedure and easier than using the vehicle belt. The LATCH anchors are positioned fairly well for easy connection to the vehicle anchors, but the seat base is close to the anchors, so depending on your car you might need to jostle it around a bit to get them connected. The seat feels stable when installed using LATCH, especially in the forward facing position and we liked that it feels like it's part of the car once attached. Loosening the strap is a little more difficult, but it isn't as hard as some and won't leave you crying or asking for assistance from a helper. Luckily, if you are like most families, you won't need to loosen the seat very often because it will likely stay in your car and only move occasionally.
Ease of Install - Belt
Installation using the vehicle belt is a little more complicated, but it still managed an overall score of 8 of 10 for this metric. This ties with the Britax Roundabout, Chicco NextFit, and Peg Perego Primo Viaggio Convertible.
The high score for the metric is 10 earned by the Britax Boulevard ClickTight and the Britax Advocate Clicktight with the ClickTight installation system that makes installing the seat with the vehicle belt almost foolproof and super easy.
Installation with the vehicle belt is easy enough to get tight, but finding the belt path is a bit convoluted and requires somewhat of a disassembly of the seat cushions. Even then it is hard to see, and some testers felt it wasn't the best for larger hands. Adding to the problem is that the lock-off won't close if the vehicle belt is too tight and if it isn't tight enough the seat will not be secure. It is a bit like Goldilocks and the three bears for finding just the right level of tightness. At one point we had to use a screwdriver to get the belt lock off open. This might have been a result of the belt being too tight, but given that some other seats had lock-offs that are easier to use it is a bummer.
Ease of Use
The Marathon earned the second to the highest score for ease of use with a 7 of 10, which tied with Evenflo Tribute LX and the Peg Perego Primo Viaggio Convertible. The high score is once again earned by the Marathon's big Bros, the Britax Boulevard ClickTight and the Britax Advocate ClickTight.
Ease of use is an important metric in our mind because it reflects the daily experience that impacts how much you will like or loath a seat.
The Marathon earned a score of 7 of 10 for comfort and quality. The high is 9 earned by the Chicco NexFit and the Britax Boulevard CLickTight and the Britax Advocate CLickTight.
The Marathon fabric is nicer than that on the Britax Roundabout and is one of the features that sets these very similar seats apart. It is a smooth fabric that is friendly to bare skin, and there is a softer more velvety fabric in the head region that would be especially gentle to the face. It appears easy to wipe clean and wasn't very absorbent in our tests. The padding on the seat is excellent all the way around, while some only offer padding in the seat bottom or minimal padding throughout, the Marathon offers a little bit nicer padding over the majority of the inside of the shell so children can be extra cozy. The infant insert adds more cushion, but it isn't something you can use for the duration of the seating life.
The seat is made using Expanded Polypropylene (EPP) for its energy-absorbing foam inside the shell. This type of foam is less common than the Expanded Polystyrene (EPS) found in most seats and bicycle helmets. We prefer the EPP foam because it is less brittle and a little more forgiving should it be dropped or bent. Also, it is more environmentally friendly and doesn't off gas like EPS, which is a big win in our book for little ones. Only the Britax products in this review use the EPP foam.
The overall fit and finish of this Britax product are nice compared to much of the competition. Everything on the seat stays in place, and it has a nice contained look about it with no parts hanging off or protruding where they shouldn't. The fabric fits the shell and frame snuggly without looking too much like a slip cover. It isn't as sleek and polished looking as the Chicco NextFit or the ClekFoonf, but it is still better than most. The bottom of the seat is not completely smooth, but there are no sharp corners or edges that might damage the vehicle seat if it rubs for a long time.
The Marathon is on the heavy side for the seats in this review with a weight of about 18 pounds. This doesn't compare to the hefty options in the review like the Clek that is closer to 35 pounds, but it is twice as much as the Evenflo that is just over 9 pounds and the lightest product we tested.
While weight isn't as important in this style of seat as it is in the infant car seats, because parents aren't likely to move the seat very often, it might still be of interest to parents who travel or frequent taxis or Uber. Eighteen pounds is probably more than you want to lug very far, but in the top 5 seats only the Roundabout is lighter with a weight of 16 pounds. On the bright side the Marathon is narrower than all but 3 products in the review with a width of 18.5 inches. The smallest width is 17 inches shared by the Clek and Evenflo, which makes the Evenflo the lightest and smallest in the group.
Almost any application would be a good option for this all around impressive option. The Marathon is an easy to install seat that has the best harness height adjustment mechanism and offers a comfortable ride that looks good. With higher than average crash test results, it is hard to find an application where this wouldn't be the best fit. Perhaps if your vehicle doesn't offer LATCH or you feel more comfortable using the vehicle belt for installation, then the Britax Boulevard ClickTight might be a better choice. For parents who live in an urban environment, the Marathon and the Boulevard might be too heavy to consider commuting in taxis with, but they are still lighter than the Clek Foonf.
With a list price of $290, the Marathon is less expensive than several others we tested. The performance and quality of the seat are great, and we think the Marathon is worth the asking price. However, should the price be a bit much for your budget, the Britax Roundabout is virtually the same seat with the exception of the height adjustment which is a re-thread version. The Roundabout is significantly cheaper with a list price of $180 and has the same LATCH system and buckle as the Marathon. The Marathon has the additional harness attachments that Britax claims absorbs some of the impact during a crash, but there isn't much else different between the two as far as we can tell.
The Britax Marathon came in second place in our review. We were very impressed with the look of this seat, as well as its overall performance during testing. The Marathon manages to hit the high points of each category with a seat that is easy to install, easy to use, and offers a simple to adjust harness system. We think being able to install a seat and adjust the harness for baby are key to having a safe seat. Add on that the daily use makes it a pleasure to own, and impressive crash test results and you have a seat that was a shoo-in for our Editors' Choice award. In short, all the Britax seats impressed us, and the Marathon stands out as a high-quality seat for a reasonable price that offers an additional margin of safety over the average seat and won't give you headaches to use. We highly recommend this seat.
Other Versions and Accessories
Britax Marathon ClickTight. Britax claims the "ClickTight" version is even easier to install and it only uses your vehicle belt with a 3 step process, and given our experience with the Britax Boulevard ClickTight and the Britax Advocate ClickTight we tend to agree. If the Marathon is your seat of choice (we did give it an Editors' Choice award), you might want to consider the ClickTight version or take a peek at our Britax Boulevard ClickTight ARB review. We believe this seat is a great choice because being able to correctly install your car seat impacts the seat's overall safety. Many injuries from car accidents are related to seats or harnesses that were not used correctly. Whatever increases the chances of a correct installation is worth a look in our book.
Britax sells several accessories for use with the Marathon. These include the following:
Cozy Greens Back Seat Mirror from Cozy Greens. The mirror is easily attached to the headrest with a flat base that fits against the front of the headrest and is kept secure by two adjustable straps. The convex shape of the mirror allows for a wider field of view, and it has a crash tested shatterproof surface. Once the mirror is adjusted, you can tighten the pivot point so that the mirror can't be bumped out of position accidentally. This mirror does require an adjustable headrest to attach properly, and Amazon users seem to love it.
— Juliet Spurrier, MD & BabyGearLab Team
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