i've been reading old threads and researching online. i'm looking for opinions on hitch mounted racks. i've decided i want one that supports the wheels like the saris thelma, cycleon or cycleon pro. the others i'm looking at are the thule and xsport versions. personally, i like the idea of the bike being supported by the wheels and locked in by the top tube with a frame hook. seems to me like that distributes the pressure points on the bike when you're going over rough roads. the xsport is the only model like that and it's significantly cheaper than the saris or thule.
mechanically, functionally, etc., is there a reason the saris and thule use a different design? is that the reason (in addition to quality) that they are so much more expensive?
lastly, the saris thelma locks the wheels in place by "cupping" them. the cycle on has hooks that ratchet down on the wheels. mechanically/functionally, is there an advantage to one of these designs over the other?