Need to get one soon as our DS is outgrowing his infant seat.
Any advice on the most comfortable?
Preferably the coolest one (DS gets hot easily in his current seat). I've heard to get a light colored one to stay cooler or a car seat cover for when the car is parked for a while.
Try posting your baby's height/weight/clothing size, plus your vehicle stats on the family safety forum. There are a lot of car seat people there and you may get more responses! Also, see related thread in this forum! A few of us posted our favorites--Radian, NextFit, also the Graco Size4me/MySize are all recommended as the longest-lasting rear-facing options. Ideally you want to rear-face until at least 2 years, but 4 years is preferable.
I have a NextFit for my 12 1/2 month old DS. We have a Honda Accord, a E350 van, Infiniti sedan, Subaru Outback, Subaru Impreza.....and it fits well in all of these vehicles (I have adult children at home and they drive the subarus, lol, I'm not actually a vehicle hoarder!) I like the NextFit because it is very easy to install, very compact front to back (for small vehicles it is great). If you need to fit three in a row across a seat, you may prefer a Radian because it is narrower from side-to-side.