You guys also have to remember Mayweather fights at 147lbs, and started his career at 130lbs. Also remember that MMA's rules effect strikers the most. Boxers are Professional athletes. MMA fighters are not. At least not yet. What I mean by this is because MMA is not at its best just yet. It is too new. Look at how many guys get KTFO. Once MMA hits a higher level, then you will see less of those highlight knockouts.
Again just my opinion, but teach Mike Tyson, Roy Jones JR, James Toney how to sprall, and a little bit of ground game, and they KO the fck out of Rampage, Liddell, and Couture.
As good as Mayweather's boxing skills are, his style is just not made for MMA
If Brock Lesnar can be a champion with less than 5 fights, any professional boxer can also.