4 by a wide margin. Graphics, animation, combat, all superb. But the real clincher, Cop AI, going on a rampage is more of a raison det're for GTA than it's story has ever been. But fighting the cops in GTA4 is more fun than in any of the other games. They wait for support, they move to outflank you they're just about impossible to escape from at 6 stars, they are actually a challenge. My best death in a cop fight was of my own doing, had gotten corned in an ally, was basically crouched in a corner taking on all comers. A police helicopter opens up on me so i pull my RPG and knock him down. I pull my rifle back out but my camera is fixed on the copter as i realize that it's spiraling right at me. It smashes into me and blows up, had to pass the controller on, but it was wild.