Product Review: Sunshine Kids Radian 80 Convertible Carseat

This product has been reworked and renamed as the Diono Radian RXT Convertible Car Seat, now available on Amazon.

This is an unpaid review of two Radian 80 Convertable Carseats that I purchased for my personal use. When I review a product or service that was given to me for free, I will always let you know. I never keep freebies valued at over $40.

In 3 1/2 months, I will have three carseat aged children. Mostly that's exciting, but when it comes to the actual carseats, it has been a little bit stressful. I drive a small station wagon that I absolutely love and don't plan to replace, yet the two car Britax Roundabout Carseats installed in it now almost completely fill the back seat. As my due date draws closer, I've become increasingly worried that we would have to replace the car - so when I saw that the Radian 80 Convertable Carseat was on sale at Amazon a few weeks ago, I jumped on the chance to buy two.

Sunshine Kids Radian 80 Car Seat
Sunshine Kids Radian 80 Car Seat

Why the Radian? I've been talking with friends, reading the car-seat tech newsgroups, and searching the Internet. The Radian 80 is the seat that everyone seems to recommend for three-across installations. Buying two brand new carseats when we are perfectly happy with what we have was painful, but not as painful as buying a new car would be.

The Good News

  • After a quick review of the manual, the Radian 80 was no harder to install than our current car seats.
  • After a huge investment of sweat, we were able to install two Radian car seats plus our infant car seat in the back seat of my car!
  • I like the sturdy steel frame. Beyond the federal minimum limits that all carseats must meet, there is no data about which carseats perform best, but this seat certainly seems very solid.
  • The Radian 80 can be used from birth until 80 pounds. We are in no rush to move E into a booster seat when he turns four and we hope to keep these seats for a long time.
  • The kids sit lower and closer to the car's seat in the Radian 80 than they do in the Britax. The lower seats make it easier for D to get into and out of her seat without help, and I appreciate having to retrieve fewer dropped items.
  • This carseat folds, which would make it easier to store than most carseats.

The Bad News

  • At 22 pounds, the Radian 80 weighs 9 pounds more than our Britax Roundabout
  • The "Super Cool" fabric doesn't seem as sturdy as the fabric on our Roundabout. If I were to order another seat, I would choose a different fabric option.
  • This seat sits more upright than most, which seems less comfortable for sleeping (though my kids have both fallen asleep in it)
  • The low seat height might make it difficult for smaller children to see out the window
  • Because of the seat's high back, the Radian takes up a lot of space when installed rear facing.
Sunshine Kids Radian 80 Car Seat Cover for Travel
Sunshine Kids Radian 80 Car Seat Cover for Travel

Traveling With The Radian 80
We have not yet flown with the Radian, but I wanted to cover this topic because experts often recommend this seat for travel. The seat folds, meaning that it is less likely to be damaged in transit than a traditional seat, and that it will fit more securely on a luggage cart. Sunshine Kids manufactures both a Radian Car Seat Travel Bag (pictured) and a Car Seat Carry Strap that lets you carry the seat over your shoulder (or with two straps, on your back).

Weighing (literally) against those helpful features is the 22 lb heft of the seat. I would not want to carry this seat through the airport. If we were traveling with carseats, I would have my husband drop me, the kids, and the seats off at curbside checkin before parking the car.

Update: A reader pointed out that the Radian works with the Go Go Kidz Travelmate, which would enable you to convert the car seat into a stroller and push it through the airport with your child sitting in it.

Overall, I like this carseat. The huge versatility in age range, and the fact that I will be able to keep the kids in a five-point harness as long as possible is a plus for me. Even if we weren't on the verge of having a third child, I probably would have chosen to upgrade to this carseat (instead of a booster) when E outgrows his Britax in a few months.

Related Links
Diono Radian RXT Convertible Car Seat on Amazon
Travel Car Seats

 Subscribe to our feed

Subscribe by email:


  1. Maria on February 2, 2009 at 4:32 a.m.

    I was concerned after reading about the weight, but I looked it up and found out that the seat is compatible with my go go kidz, so I could take it through the airport. I might get one. We also have a roundabout, but it is hard to travel with via car due to the height-- my son can't reach anything off the seat on his own! Maybe this one will be better?

  2. amanda on February 2, 2009 at 1:13 p.m.

    I'm curious as to whether your kids can buckle themselves in. My son (3.5) can buckle himself fully into a Britax Marathon but not our spare Evenflo (the buckles on that one are obnoxious even for me!). It saves me a lot of time and effort when 2/3 of the kids can do it themselves, but I was considering getting a Radian 80 when he outgrows the Marathon....
    Thanks Debbie :)
    Amanda @ &

  3. Debbie on February 2, 2009 at 2:11 p.m.

    @Maria - Great point! I don't know why I didn't think about that
    @Amanda - It took E (3.5 years old) a couple of days to be able to buckle himself in, but he cannot undo the buckle (he could in the old car seat). D can do the top, but not the bottom - which is the same as with the Britax. The mechanism for loosening the belt is easier than it was with the Britax, and E can now do that himself too.

  4. Michelle on February 18, 2009 at 8:46 p.m.

    I'm having trouble with deciding on a convertible car seat. Right now I only have 1 daughter. I just purchased a britax boulevard cs and I think it fits ok (rear facing) but it's definitely tight and not sure I have a secure fit in the middle. If it's on the side, my husband is completely uncomfortable if he's in front of it. So, I'm thinking about sending it back for a Radian but the length of the Radian rear facing concerns me. Would it even fit? I drive a Prius. Thanks for any thoughts.

  5. Debbie on February 18, 2009 at 8:53 p.m.


    Unfortunately I'm not the best person to answer questions about how the Radian would fit in different cars. I've had great luck with posting at this forum though:

    Lots of car seat techs hang out there & you should get an answer to your question.

    Good luck!

  6. amy on February 9, 2010 at 8:03 p.m.

    I bought a radian 80 last year, for my 4 yr old. It has been a great seat. It seems sturdy and I love the fact that my son can stay in a 5pt harness longer. my only problem with it, is the weight. It is on the heavier side, but I rarely take it in and out of the car. Overall I am very satisified and would highly recommend this seat! I am getting ready to buy another one for my 3 yr old.

  7. Meave on July 19, 2010 at 11:49 a.m.

    Quick question for Michelle,

    I am trying to decide on a RF car seat for my son. He is now 20 ibs. Did you end up trying the Radian in your prius? If so, can you let me know how you fared?


  8. Debbie on July 19, 2010 at 12:11 p.m.


    My friend has two Radians FF and a RF britax in her Prius


  9. Patti on June 27, 2011 at 2:17 p.m.

    Am trying to decide on a car seat, am looking at the radian 80. Have a Honda civic 4 door and am currently using a grace behind the passenger side, when people have put the radian in where is it that it seems to have to go? will it fit in my car, what's your opinion?
    y daughter is 5 months and reaching 6 mos soon.........

    just need some advice!

  10. Debbie on June 27, 2011 at 8:42 p.m.


    Forward facing it would fit in your car well, but it does take up a lot of space rear facing, and you'd have to experiment or ask on one of the carseat forums.

    Good luck!

  11. Amy on August 15, 2011 at 10:24 p.m.

    I have been doing researches on choosing a car seat to travel my kids. Thanks for sharing information. Great review! Sunshine and Britax are both popular brand on the market and thanks for comparing them. Help a lot!

  12. ana Paniagua on March 13, 2013 at 10:11 a.m.

    help. my friend gave me her used car sit i will like to know if it's till safe to use. i was told that car sits expire? the MODEL US185500