We own a Durango...which seats 7. Not comfortably but it works for how often we're in the car as a family, which isn't all that often.
The backseat looked like a row of sardines with carseats lined up and overlapping at some points. They fit in that they were all securely bucked but not well enough that we were comfortable living the way they were. And worst of all we have to pick the baby carrier up so high to get over the other seats we were killing our backs just getting our still pretty tiny baby in and out of the car.
So with our tax money I splurged on two new much lower profile seats (Radian 65 SL's from http://www.albeebaby.com).
The boys were so excited to see their seats come in the mail they wouldn't get out of them after we adjusted the straps.
But we finally got them out of them and installed them in the Durango and took them for a test ride.
I'm telling you...these carseats are awesome...even our 7 year old fits in them...