I have forgotten more about Duran during my morning dump than your demented old ass will ever know deal
Actually Mayweather is the naturally bigger of the two. Floyd's taller by about an inch and has about a 3 inch reach advantage. I'm guessing at these numbers but I know they're close and given that Duran weighed 156 when he fought Barkley makes it a pretty valid comparison. That truly is a fight for the ages, I've lost track on how many times I've seen it but I never get tired of it.
You actually have to have watched the Duran-Barkley fight before you can answer it. If you did, I can't imagine you have the same answer. Duran when to war with a guy that was 6'1" (Duran's 5'7") was younger than him, stronger, had way more power, and had just beat Hearns for the middleweight belt. And Barkley was trying to avenge a lost for his late friend Davey Moore, who Duran pretty much destroyed at 154. It was a war he won because he just wouldn't go down no matter how many clean shots Barkley hit him with and Duran had enough of his own power to hurt Barkley and drop him with a 4 punch combo in the later rounds. It was fight of the year and rightly so and it my books it was Duran's best win and one of the best ever.
Floyd wouldn't be able to deal with the intensity of Duran, even at the age of 37. Especially if Floyd fought the way he did last night, he's slowed down and I saw his feet going all over the place when he was missing punches. With Duran's ability to roll off a punch and counter with hard shots he would trouble Floyd. Only way he would win is if Bayless is the ref and it ends in a disqualification from a few too many left hooks to the balls by Duran. It's a shame we don't have time machines!
Some versions above 154 would loss to Floyd but the Duran who beat Moore and Barkley would also beat Floyd.
Duran was fighting at 168 at 37..Mayweather fights at 147. Duran was quick on his feet although he was chubby.
Duran was so inconsistent and Floyd's consistency is among the best ever, it's hard to pick Duran especially if Floyd's strategy is to avoid the ropes. I have no problem picking Duran at 135 though