As a fellow 360 CoD player, only about 1 person in every 2 to 3 games I play has a modded controller.
Oh and modding the controller can be done on any console. It just makes the input device send the signal of many inputs (such as a trigger pull) at a time rather than just one.
Even with a modded controller, it doesn't help them. They are usually still very sucky and as long as you play smart against them they have no advantage to using the mod.







