Yeah MaxiRiders are quite wide. We have a Rav4, so not a wide car at all. The 3 seats we have are: DD1 will be in a Infa Secure Ve Lanti Adjustable Booster Seat, DD2 will be in a MaxiRider, DD3 will be in a Go Safe Ether Convertible Car Seat
The Infa Secure & Go Safe were the slimest seats we could find.