Like most people I was a fan of the Black Ops engine. The screen was perfect and most of all I felt 100% comfortable with my sensitivity, then MW3 was released. I find the MW3 sensitivity to be a tad over the top in speed and general sensitivity. I play on 3 sensitivity and the difference between BO and MW3 is huge, which is now becoming a re-occuring problem for me so I had a little look about the settings when i noticed the HUD Horizontal and Vertical margin lines were fitted perfect to my screen. After a few alterations, I found that reducing the HUD causes me to personally find in-game a lot more stiff and controlled. Don't ask me why or how as I don't know the answer, all I do know is that fully reducing the margin lines so the HUD is more centered helps my personal problem of the MW3 sensitivity being too much. Summary: Instead of putting your Horizontal and Vertical margin lines to the edge of your screen, reduce them fully so there is a visable transparent square on your screen, try it in game and enjoy. I hope this works for you as it has really helped me.