I think Stevenson and Kovalev both have such good KO power that either could KO the other, so I think it depends who lands big first. Neither man is accustomed to his fights going the distance (Kovalev's longest is eight rounds) and Hopkins is wiley enough to drag the fight out to get the decision. Any of these men can conceivably beat the others, I just hope that stupid boxing politics doesn't prevent us from seeing these fights!
Hopkins only targets guys he think he can see something he can exploit - and I thought this was fight he was looking for. If Bhop can see something who am I to argue