Long-term car seat planning - or - embracing vs. avoiding the combination seat


New member
When we were searching for a convertible seat I focused a lot on maximum weight and height limits. For this (but also many other) reasons, we ended up with a Sunshine Kids Radian XTSL. I'm happy with the seat.

It occurred to me, though, that with the existence of seats like the Graco Nautilus and Britax Frontier, that other shoppers needn't be too overly concerned with maximum forward-facing limits of convertible seats, yeah? They should just figure out which convertible seat allows their child to remain rear-facing the longest. They could plan to do convertible seat, then combination seat, then . . . backless booster? Of course some of it would depend on the dimensions of the child related to their age/maturity/readiness for a booster.

So, what seat do graduates of the Radian XTSL tend to go to next? High-back booster? Backless booster? Would it be fair to say that the Radian should allow us to skip the combination seat altogether?


Depending on size, the XTSL can last until you need a HBB. Once in awhile, you find a child that is not old enough, or mature enough, but really, for hte most part, most kids will be fine.


New member
If your child is average I would say yes they most likely won't need a combination seat. My brother is 8 and still fits. His normal seat is a high back booster though. My daughter is only 4 and on the top harness slots. My son is almost 2 and would likely be on the top slots as well if he were ff. So you can see how different kids all have different needs.

I like the combination seats because they keep kids harnessed longer. But I see to many parents going from infant seat to a nautilus.


New member
It depends on the age if the child for me. My 3 yr old has a 16" torso and is just a hair from outgrowing her Marathon, which harnesses to 65lbs. So she is going into a combo seat. If she had made it to say 7 or 8 in another convertible seat I may have concidered just going to a lbb depending on size and maturity. I think most kids need to slowly get used to more freedom in the car so I wpuldnt skip the hbb step for my family.


New member
It really depends on the kid and the family. My 4 year old has an over 17 inch torso and already outgrew her radian (while SK/Diono allows use over the top harness slots I was not personally comfortable with that). She is incredibly mature and safety conscious/compliant so I tested her for a while in a high back booster before she outgrew her radian and determined I could trust her to sit correctly 100% of the time (the radian was in our trunk ready to be brought out at a moment's notice and she knew that).

I'm not sure what we would have done if she hadn't been booster ready as I had tried the nautilus and frontier when purchasing the radian and neither fit in my car (a beetle, we only have one car). Since then the maestro came to the market, but that wouldn't have offered much time after the radian was outgrown so might not have made sense even if it fit. Luckily she was perfectly behaved for every ride so I moved her to a booster.

Her sister has far less impulse control than my first did at her age (2.5) and a penchant for mischief and testing the rules, so I'm thankful that she has a proportionally shorter torso and we'll be getting a larger car soon so if she outgrows the radian early we can get a frontier for her. I know she'll be far far older before I can consider a booster.

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