Fujita, Hunt, and Fedor are all good nominees. I'd have to go with Hunt right now. That dude's head is made of concrete. I havent seen anyone take Cro Cop's LHK like Hunt has.
Fujita was KOed by Wandy, good chin but not the best. The only fighter who was hit with Cro Cop's Foot and not KOed was Mark Hunt. Clearly Hunt has the best chin in MMA, he's never been rocked and he was a Kickboxer first, competing with the best in the world. End of thread!!!
Cabbage took everything Tim Sylvia could throw and was still standing. Watch that fight again, Cabbage is a tough sob. Hell Sylvia even clinched him and kneed him in the face and body and Cabbage still wouldn't go down.
Just imagine Arlovski with Cabbage's chin. A very dominant UFC heavyweight you got!