Darn, makes me wish I had installed GTA IV on this computer sooner. I know Just Cause 2 allows you to ride (literally ride on top of them) and fly planes, helicopters, boats, and cars. So in that sense it is more vehicle friendly than GTA, where getting to a plane takes quite some time, for me at least. Plus you get a grappling hook in JC2 which is just plain fun. Both are definitely fun in their own freeroam options. GTA is a city freeroam, and JC2 is a more open-ended island freeroam with a few towns and one somewhat large city.