Ditch the black mouse pad - The g9x works OK on black surfaces but the original G9 absolutely fucking SUCKS on a black pad.
It's not apparent at low speeds, but try making a quick drag across the pad and watch your mouse cursor. It'll start flicking back in the wrong direction.
This issue has been doing my head in for a few months now but I never twigged that the pad colour was causing it
My point was that with any mouse, a black mousepad will cause the optical sensor to work much harder than it needs to, as evident with a wireless mouse for example, by a measurement of its power usage.
Result of this switch is that I can now target full-speed flying hunters accurately in L4D2, whereas before I had to pin their landing spots and couldn't track them in the air.