G.R.A.W is probably the game I've played the most on the Xbox 360 so far. The campaign is a lot of fun singleplayer, and the multiplayer is insane, especially the co-op missions (well, they were until Xbox live went all weird and the games started disconnecting, but whatever). Nonetheless, when I heard it was available on the PC I wasn't really that interested. I mean, I've completed the campaign already, and I have it on the 360, so who cares? Well
apparently the PC version is a lot better than the 360, and it has enough differences to warrant checking it out.