Kimbo is a good brawler, but he hasn't fought anyone good. All of his fights have been with bums. Hell, he got lucky in his last fight against James Thompson. James Thompson is almost a joke in the MMA world; he's huge but has a glass jaw. Kimbo was getting man handled by James Thompson, and if it wasnt for Thompson's ear exploding, I think Thompson had a good chance of winning.
His fight before that was against Tank Abbott. Tank is what, 45 years old?
Before that, he fought some other guy and before that he fought Ray Mercer who came out of retirement to fight Kimbo.
Put Kimbo in the ring against someone like Fedor, and I'll put money on the table that Fedor embarresses him in front of the world.