a girlfriend of mine has a Chrysler wagon (not sure what it's called), but she can have 3 car seats on back row, two in middle and then the driver and wife or whatever. She told me to make sure there are anchor points in all rows (as we're going for a 7-8 seater now) and find out how many each row is allowed to use at once. Apparently just cause they have the points, doesn't mean you can use them all at once as it stresses the seat structure too much if there is an accident.
Food for thought hey? We're looking into the Kluger as My older two will be able to use boosters by the time we have the third. We have a booster with an anti-submarine strap so Jess can use that when the time comes as Kat now understands why she has to sit in the seat.