Retro,
Well you got me there. I have yet to own a mini van but probably will some day. Can't argue the piece of mind of securing a bike inside the vehicle while running into the grocery for post ride munchies. Guess I should have elaborated on my personal experiences more. Many of our tandem rides are off road and the bike is covered in mud when we finish. Even wiped down, I would not want the knobbies on the carpet. When we do mellower rides as a family the back seats are filled with 3 boys and a dog (thus the tanker family vehicle we currently drive). I would still stand by a roof mount as my favorite way to transport bicycles. Hopefully you didn't take my statement literal as far as "nothing beats up a vehicle interior like a tandem". I know the bricks I was loading in my brothers car last month were worse. Shoot, on a good Saturday even driving the kids and their friends home after a muddy soccer game can be messy.