Brown
I don't know why anyone hasn't brought this up already. Ronnie was a back up to Cadillac Williams for most of his college career. While he did do well spelling him last season and creating a two-headed attack, not to mention filling in when Williams was injured, I can't be too confident in our new starting running back having been a back up in college. He definitely has a lot to prove, and hopefully his pass catching ability will be a huge benefit to his career here...Especially considering I'm not at all confident with our QB's...
Anyways, I think this question is very case specific for each team. Dillon was the perfect fit for New England because he's a power runner and they have a good O-line. Martin, I think, is the overall best and could work out anywhere there is a decent O-line (not here). McGahee has the most potential and would have been a top-3 pick if he hadn't blown out his knee. And don't tell me when he was playing down here at Miami that we wouldn't have all loved to have him, especially if we had known how RW would have turned out...I like Ronnie for the 'Phins though because he's a big guy and with our shoddy O-line might be able to create something. He may not have a good season this year, but once we get an O-line he should be pretty dominant. He's the best fit for our team, but in my opinion probably third or fourth best.
I'd go: 1) Martin-but only for this year, 2) McGahee, 3) Brown, 4) Dillon-just because he's older and benefitting from an O-line better than the rest of the teams...Screw RW