I have two of these car seats and two babies that are super happy to fill them :)
One of my twins was born at a tiny 5 lbs and went down to 4.5 before gaining weight, she fit into the car-seat very well!
The detachable head support was very reassuring that their little heads did not twist or "flop" over when the vehicle turned. When they out grow the bean shaped support pillows, they come right out and your baby's head is still supported by the secondary support pillow. Eventually (around 5 months for my babies) you take out the secondary support. The "air" cushions seem to assist in comfort from that stage :)
I have not noticed any pinching or issues at all with the harness between my babies legs...

The base is SUPER easy to install! Especially if you are using the anchor system! There are pictures on the base and really you just would have to try to get that wrong..

The material is very durable so far (7 months) no rips, or unwinding. That... Read more

There are so many options these days when it comes to car seats so you want to make sure you research and find a car seat that will work for your family and baby! Safety 1st helps you to start your little one off on the right road with the onBoard 35 Air Infant Car Seat featuring Air Protect Side Impact Technology.

"Safety 1st engineers designed Air Protect using next generation testing methods that simulate the most violent types of side impact crashes, those with vehicle intrusion. Using this advanced methodology, Air Protect was engineered to defend your child in two vital ways. During a crash, the system immediately shields your child's head from the impact. In a second layer of defense, Air Protect allows air to escape from the headrest: channeling crash energy away from your child, creating more ride down time. It is this double layer of protection that makes Air Protect technology unique."

That's a pretty confusing method but basically what it means is... Read more

This seems to be a very sturdy and safe car seat. My only complaint is that there is very little leeway on the harness between the baby's legs. Its nice to know my baby is securely fastened in, but if she gains much more weight on her thighs (and she is currently a tiny 5 1/2 pounds!) it looks like these have the potentisl to dig in and pur pressure on her legs where the plastic clips are. Still its early days and I am still figuring out this seat - maybe it will be easier as the baby grows into the seat some more!