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I'm using a Naga, I'm starting to wonder if it is some kind of momentary huge loss of FPS in the game though (Even though FRAPS doesn't seem to be picking it up), I've noticed that if I turn off SSAO in the graphics settings it not only gives me better FPS, but the mouse controls better. It still doesn't feel right, just better.
Try putting image quality at the highest setting and turning other features like shadows/disrortion/filtering etc all off.
I presume you also have the Razer Synapse installed? Perhaps try testing with another mouse to see if it's isolated to the Naga or is a wider problem.