I use the X1's right now. I think it does make a difference. You can hear footsteps, people moving through plants, reloading, etc even better and that can make the difference.
Going back to learning the maps discussion, I found it easier to learn these maps over the World at War maps. When I first played those I was so lost but MW2 didn't seem that bad. But there are many different things to learn about each map. Good places for tactical insertion, crates, routes to take, etc.