I agree with both of you guys. For me it was a sim. My best PS3 PES game.
But in PES2011 you could backheel all day long, could shoot from anywhere, and could overhead kick/bicycle kick from anywhere outside the box and get it on target. The gamespeed wasn't slow either.
So what makes something a SIM?
The only notable thing about PES2011 was the passing assistance, it's default wasn't very assisted at all, it was almost manual, it was lovely.
PES disqualified itself for me by the horrendous CPU defensive AI which made it easy to trick yourself through on goal with easy, repetitive one-two´s.