I'd say Peter! To me Homer is like a dofuss and dim-witted. Peter is more of a sick twist, who would do sexually perverted things to his wife. I don't get that vibe with Homer.
Homer.
According to Marge homer was a Mac in the sac. and because it was an older cartoon they couldnt show the things that prove Peter sucks in bed. Peter got off in the plane and they werent even undressed or doing anything. He kept going at it while Lois was having a heart attack. And the fact that lois can say "Awwwww, good for you!" sincerely after he gets of and she doesn't almost tells you that she knew she wouldnt get hers when she starts it.