In my opinion, 1k dpi and x2 in game way too much for 1600x900. I have the same resolution but I use 800dpi and x1 in game. Not really moving my mouse too much on pad. Like 5 centimeters or so. And yeh, ofcourse you are will be like a chicken on the ice when you cut your sensitivity in half. Also, ppl using x1 sensitivity in-game coz it will be the same sensitivity as in windows, so you wouldn't feel any changes while you in-game or just sitting in browser or doing something else in windows.