I think Abraham is the better fighter, but I'd probably have to pick McClellan by KO here. Abraham is brave as hell, but way too much firepower for him to wade through in order to do what he'd have to do to win. He's the better boxer of the two (at MW, as people will point to the Dirrell fight to argue to the contrary), but not enough to where I see it being the difference here.
I actually think McClellans style suits Abraham, as Arthur likes his opponent to attack, stay behind that turtle guard and then fire back. McClellan could also be hit and Abraham's punch would definitely hurt him. The question is, can Abraham's defense take G-boy' full arsenal.
AA does NOT handle body shots well, and Gerald knocked out a large number of opponents with his left hook to the body. And although AA does have a good chin, Miranda and Taylor punch nothing like G-man. Whereas on the other hand, does AA hit any harder then Jackson, and Benn? No.