We squeeze in 2 boosters (Infa secure kid max) and a Safe n Sound baby seat into a Commodore but it is tricky doing up all the harnesses (as we have the protecta harness with the seat belts of the car). Have it all sorted in terms of how to do it but I have to jump in the back seat along with the 3 kids to do it and it is not fast! Having said that once in they are fine. The main issue is the contour of the cars actual seats, if they were flat they would be fine!