I've got to be honest here (and will probably get slated for it) I don't think anyone beats him at 130lbs. Arguello had the best chance imo but i think Floyds movement, hand speed and timing would have give him fits.
Of the guys I've seen a decent amount of footage of at 130, I'd give Chavez the best chance. I like his chances more than Arguello, although I'd hesitate to pick Chavez over Arguello at 130. Camacho has a decent chance with his outrageous speed and talent but I think Floyd makes the proper adjustments and prevails. Once he started landing with some regularity, Camacho's survival instincts would take over. Floyd would be in it to win it, Camacho would be looking to last the full distance.
Comacho would have been a hell of scrap ..Floyd has never been in the ring with a prime fighter that could match his speed ..That would have been a good scrap ..
Armstrong & Chavez. There are a few guys, like Duran, who never spent much time at the weight but I'd still favor. Not many though.
Forgot about Camacho...He might get real close on a bad night for Floyd..If it took May a few rounds to adjust Judah then a faster, more durable and I think actually less mentally fragile version will likely do better. ...Hec had swagger at 130 and pretty good stamina...No way May hits like a lightweight Rosario, he would have to put a bit of sustained punishment on Camacho to get him to ***** up that good..and he could drop a few rounds before he gets to that stage.