I just tried rinput in ql for fun (http://fnatic.com/downloads/662). quake live is different from other games so had to look for a work around to make it work. This is how i got it to work.

First i launched ql and set in_mouse 1 in my config. Then i made sure to join a game before launching rinput because rinput messes with the ui and makes thing unclickable. Then finally i launched it and typed quakelive.exe to console. After playing around between in_mouse 2 and rinput a bit i noticed rinput felt higher sens yet i reached the same 360/cm.

This means either rinput has some weird accel or ql input is bugged and the faster mouse feeling is from less input lag.. Am i just imagining things or does anyone else feel this too?