We recently purchased this seat to replace our carseat that was damaged on a recent flight.
br /I figued we would get a seat that would also be a belt possitioning booster so that we wouldn't need to buy another in just a short while.
br /I have been using the seat for 3 weeks and will be returning it in the morning. The shoulder straps have come unhooked from the back of the seat twice! Luckily both times we weren't driving yet. I put my daughter in, buckled and adjusted her. Got in the car myself and my daughter pointed out the strap was undone. not from the buckle, but it pulled all the way out from the seat. I had to take her out, take the seat out. Then rethread the shoulder strap. Quite a safety issue.

I recently purchased this seat for my son. It takes forever to get the cover off to wash it. You have to unscrew a number of parts. The tether strap is a terrible design. You have to thread it through a certain way or it doesn't hold. I have yet to figure the "right" way even following the pictures in the manual. Also the latch does not hold the seat as tight as I would like, but the seatbelt does.