Just reporting success by reducing my report rate to 200Hz (and dropping my DPI to 200 as well, but that was just to fix the speed), on a Logitech G9. 500Hz was too high and very droppy, didn't try 250Hz. Left all the sensitivity settings in-game at their defaults, whatever those are.
Made everything very smooth and playable.
For mice that can change report rate, the Logitech SetPoint config program lets you do it (per-profile on the G9, I now have that in my "old games" profile that also maps buttons 4+ to keystrokes so that I can actually use them).
Logitech site suggests that SetPoint 6 removed 500Hz from the options for the mx518, but that it is available in 4.8; implication is that lower rates are available in either.
http://forums.logitech.com/t5/G-series-Gaming-Mice/Enabling-Report-Rate-on-MX518-and-Windows-7-x64/m-p/439179 So you should be able to do it in SetPoint.