I use a standard controller and play on a 24" monitor (that Asus 144 hz one), and I use a sensitivity of 3. I do pretty decently, but I dont snipe too often unless it's on certain maps. I have a k/d of 1.7 on my Hunter and 1.5 on my Warlock (which I've been improving lately). Edit: In my last five games I had k/d's of 2.11, 3.40, 2.33, 4.20, and 8.25. Using Ill Will or Red Death and Low Grade Humility or Matador 64 depending on the maps.