Love the slim design of the car seat. We have taken our Diono with us in several cars and rental vehicles. With the use of the angle adjuster (purchased separately) I am able to install in smaller vehicles (2009 Kia Spectra) with plenty of room for my large 5'4 frame and still allow more than 12" between myself and the front airbag and room for the passenger as well. We have also taken the car seat on the plane, with narrow seats. It fit quite well, but I would HIGHLY suggest purchasing the backpack and additional strap, as it is HEAVY! I'm a single Mama and dragging a 30 lbs kid and a 30 lbs cars seat. Better if you're installing in one vehicle and leaving it. LOVE LOVE LOVE the rearward facing tether, which limits the head excursion in an accident, as so few American car seat manufacturers offer this safety feature. My child is still REARWARD, having turned 6 this month (38 lbs and 39.5"), and is still fitting within the specifications for rearward, let alone the 90 lbs limit for forward facing. When forward facing a friend's child in the vehicle, it allowed other passengers ability to freely pass through the rear seating space, and allowed him to even rearward face at 4, and 48 lbs and 42" (he's a big boy). As previously mentioned, the ratcheting system is a pain, wish it could be better, and a no-rethread harness would be a Godsend for this.. We have had the Radian car seats since our first Sunshine kids 80, and have loved them ever since.