My most favorite to just ride...that would have to be the '93, 600 Kat. That thing rode like a dream and ran really well for it's age.
Most fun to screw with people thinking it was slow, the '90 Radian won that one hands down. That thing ran great when most wouldn't expect it.
My latest ride, the '01, 929, is quickly becoming my favorite so far. If I could just get used to the power wheelies, then I will like it much more.