Unreal Engine usually does a good job of scaling down on lower end computers and still managing to run pretty decent. I have cod4 for 360, and I havent played anything quite as addicting in a long while. Also, I downloaded the demo for PC and it ran surprisingly well, albeit only in 1024 and 1280 res, with 2x aa on, and with most everything turned up to 2nd highest or highest quality, and my pc is 2 years old, but it was the top of the line when I got it. It looks even better on the pc I would have to say, but there are certain things in the 360 version that definitely look prettier. I think the higher resolution was what really made the pc version look better, or sharper would be a better term, but the game still stuns on the box.
Currently Playing:
PS4 - Killzone:SF and Assasins Creed 4
XBox One: BF4, CoD:Ghosts, Dead Rising 3, Forza 5
Changing channels with my voice: priceless!!!