The only thing Margarito can dominate is the can of organic fruit juice he's desperately trying to sell alongside Capatello in the streets of Tijuana.
williams pac mosley would give him hell and likely beat him.... marquez will be a very difficult fight and can win on close points... cotto would give him a decent fight but likely lose... margo is too slow and podgy...if cotto schooled him for 1/2 a fight, mayweather will be worst.
I think Pac would have his most intense training camp for that fight, and would be determined enough, but that still awaits. I think Mosley would get countered all day long and picked apart like Winky did him.
Williams and Pac. Mosely is an easy match for Floyd, so is Cotto, Berto, and there isnt ANYONE other than Pac at 140 worth mentioning. People seem oddly delusional all of a sudden about Mayweathers vulnerability. This isn't a guy who is going to lose to anything less than an ANIMAL with skills. Pac and Williams are those animals, for entirely different reasons.
Williams would be interesting because of his reach. But I could very easily see him getting frustrated and a little wild.