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I don't know how to describe it.. It's responsive, and tweaking the sensitivity can help somewhat but the mouse in general just feels wrong.

It's almost kind of sluggish and innacurate. I don't know if you guys are aplying some smoothing or acceleration but it gives off the feeling of "Requires effort to keep it on target' when it comes to moving the mouse around the interface and stopping it exactly where I want to click something, etc.
We don't actually use any additionla acceleration but mostly rely on Windows setup from an individual player. How is it regarding speed of movement?