Oh yeah, I totally forgot GSP on my list, my bad. He's 27, 2 time world champion and a nice and humble guy to boot.
But he wasn't always humble and a nice guy. Every single UFC fighter is going to talk cocky about there opponent at one point or another. Amir is very humble, but if he's ever on a PPV, they are going to make him say how he's going to destroy, KO, punch their face in, etc...CB to me is no different than the vast majority of other UFC fighters.