Over the years, I've had 4 Britax in two different cars plus everybody in my immediate family had them for DD as well. Loved them and have nothing bad to say about them.
Diono will last a lot longer. I have never had a britax convertible car seat. I have the infant seat, and frontier 85s. They have a short harness and a lower harness height.
I have two diono rxt's. Leah was five and a half when we turned her forward facing for convenience. She still has five pounds and another inch and a half before she grows out of it rear facing. I have my two year old nephew rear facing in one currently. Yes the seat is a bit harder to instal. But if you are not a car seat tech I would recommend getting it installed by a professional.
Not the Britax. They are nice but don't last very long because the shell is short. I know this isn't on your list but 2 of my favorites are the Peg Perego convertible and the Chicco Nextfit. I had a Radian and returned it because I hated the ratcheting strap but a lot of people don't mind it.
We were 2 under 2, now 3 under 3!
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I wouldn't do Britax. It has like one of the shortest shells on the market. The Diono has the longest I believe, so it will take a long time for LO to grow out of it. We went with the True Fit Recline and really like it. It's not as long as the Diono, but still very long.
I like our Britax Marathon, and fortunately DS is small so the short shell is not a major concern. The seat is comfortable and easy to install. However, if I were in the market for a new primary convertible seat, I would be looking very seriously at a Chicco Nextfit.
Re: Convertible car seats- STMs
Diono will last a lot longer. I have never had a britax convertible car seat. I have the infant seat, and frontier 85s. They have a short harness and a lower harness height.
I have two diono rxt's. Leah was five and a half when we turned her forward facing for convenience. She still has five pounds and another inch and a half before she grows out of it rear facing. I have my two year old nephew rear facing in one currently. Yes the seat is a bit harder to instal. But if you are not a car seat tech I would recommend getting it installed by a professional.
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