Diono seats are known for being FAA-compliant, fitting in vehicles in rows of three, and accommodating rear-facing for much longer than many competitor brands. However, they can be a bit challenging to install and take up a lot of room rear-facing. To choose the best Diono seat for your child, you’ll want to consider their current size and weight, how old they are (IE how long the seat will last), their torso length (this is the deciding factor fit-wise for older children/those at the upper height limit), and what vehicle (and configuration) the seat will be installed in.