Who has the Best Resume for Undefeated Fighters?

List all the undefeated fighters and their accomplishments. Marciano, Calzaghe, Ottke, Mayweather Jr, etc. I'm just wondering if the "O" makes that big of a deal given many fighters have lost to great competition; and of course when they lost they might not have been at their best; like Ali losing to Frazier after a 3 year layoff and never being the same fighter he was pre-exile. I'm not so sure Ali loses to Frazier at his best/pre-exile. And yes, I bring this up because of Floyd :) I like Floyd but I'm just wondering how many people years from now are going to use the "O" enough said bit like they do some others. For me, Floyd needs to do a lot more like beat JMM, Pac, Cotto/Shane, etc... And even then, he isn't the best but it will boost his legacy up a lot. But does he have a chance to be the best undefeated fighter out of the list or is he already?