I'll go with Quartey although i can see Williams providing him a lot of problems. He tended to fade and Tall Paul could go at a torrid pace. I'm thinking Ike's thudding jab and William's less then stellar defense allows Ike to put a lot of rounds in the bank. Williams comes on late but it's not enough. 115-113 type of thing but the actual scores would vary a lot.
I've only really seen three Quartey fights. De La Hoya, Lopez and Vargas. I think Williams gets stopped here, but the point about Ike fading is a good one IMO.
None of the those 3 exhibit Quartey at his best. Better to check out circa 94-96 Quartey performances.
Just watching his fight with Phillips; looks like the inactivity may have effected him in his fights with Lopez and Oscar. He seems sharper and quicker here, fresher. If he kept pumping that jab out, firing the cross and turning over that left hook, he'd stop Williams at some point IMO. He's also much, much tougher and stronger. Unless his stamina was much better at this point than it was in the De La Hoya fight, I still think Paul has a chance.
Not sure about Quartey stopping Williams. He was a solid puncher, but not a devastating one, amd tall paul showed an excellent chin through his career (the martinez ko notwithstanding)
I'm thinking that the accuracy, and constant heavy-handedness on Paul's non-existent defence is what gets the stoppage, more than pure power. Sort of a bludgeoning.
Quartey was better against fighters that came to him. The way he leaned up on his left jab made it hard for him to move. But,if you come to him, he can lean into the jab, then settle back and throw other punches.