Difficult question, mayorga in his prime probably, until he ran into tito he was ironed chined but tito destroyed his chin much like mosely destroyed margarito's chin last night, and as much as i love shane he is not anywhere near the puncher tito was, i'm not sure he would have KO'd the pre tito mayorga
im gona say what i sed last week "margos chin is total granite, like he can take a sledgehammer and walk right thourgh it, didn't you guys see wat cotto was thorwing at him"
If Mayorga had fought Margo in his prime at 147, there is no longer any doubt in my mind that Mayorga would've beaten Margo. He was similarly a beast at 147, and wasn't K.O'd until he fought Trinidad at MW (I might be wrong, going on memory not on boxrec) I always thought Margo would edge it due to his superior chin, but I know that it isn't indestructible now and say that Mayorga has the better chin, as he has been in there with better punchers and I know how much he can take. I think if Margo had fought Trinidad at any weight he would have been stopped.
A prime Mayorga hands down. He offered up his chin to a Prime Tito and took it. Margo would have gone down from that shot.
about the same, remember, mayoga has fought bigger punchers then margo so the fact hes been koed more can be overlooked.