I have 2 concerns about it, and it's based on speculation. I imagine if something additional was needed for angle, it could be hard to use with the shape of the front of the foot. I also wonder what the lock-off is like to use - I could see it being difficult to open if the seatbelt was super tight already when it was shut. I haven't installed one before though, so this is just what I wondered when I looked at it..
The other thing is it can't be used without a base, and apparently extra bases aren't available for purchase yet?
It's light weight though, and has a nice angle indicator. The handle is comfy to carry, it seems like the shell is a decent height. Overall I think it's a nice seat and $200 is a wonderful price. It would be a contender for me if we had another kid just because of the 4lb min weight limit. But I reserve the right to change my mind once I've actually installed one and/or seen a kid in one.