Probably too late now, but I thought I'd throw it out there. I have 2 Eddie Bauer sits in the back of my X5 - a rear facing seat for my 3 months old son and a convertible forward facing seat for my 2 year old daughter. They fit in there just fine, but there is no room there for much of anything else. Britax makes some of the best seats out there, but to be honest, Eddie Bauer seats have improved dramatically and don't give anything up to Britax, at half the cost. If I were just getting one seat - I would have considered a Britex; since I had to get 4 seats (2 kids x 2 cars), the price difference was really apparent. FWIW.