Some people say your first choice is usually the right one, and most people, and I'm sure most of us here think Floyd is about to embarrass himself, but I always remember what George Foreman said about Mayweather earlier in his career. Foreman called Mayweather a "natural", and said it's rare you find a guy who's a natural fighter. With that said, that makes me reconsider Floyd's chances. There's no way he's going to master MMA in 6-8 months, but the fact that he's a fighter, a natural talent at it, makes me more and more consider the possibility that Floyd would still do well in MMA, and maybe even in UFC.
I knew Conor would do well in Boxing, because he's still a fighter. I never thought he'd beat any top guys, but he's still going to be in there and make boxers think and question decisions they make or be punished for it. At the end of the day, a fighter has developed an instinct to deal and avoid damage, and that's something that carries over, even if it isn't masterful in that profession.
There are some MMA events that aren't as evolved as UFC, and you see guys who aren't jack of all trades, you see pure wrestlers, pure boxers, pure kickboxers, pure karate, etc. And some of these guys still do well against a style they're not trained for, because they still have a talent for fighting. And that makes me consider, Mayweather being a natural fighter, maybe he won't do as bad as we all think.