As far as fitting in a vehicle and being comfortable...Most cars are somewhat uncomfortable for me to sit in for long periods, but we recently rented (well, AAA rented it since our Sebring was in the body shop because some girl backed into it) a Chevy Cruze. Overall it was comfortable (good seat shape), but there was a lack of a good place to put my knees while the cruise control was on (I'm 5'10" about 180lbs - I think I'm smack in the middle of the 95%).

I haven't sat in any of the modern pony cars, but it appears to me that they all have doors that are too tall (I think this is for safety).