Do you actually use the mouse at high DPI settings? For most people, assuming they have their "Mouse sensitivity" control panel option to default (centered), 2000 DPI is plenty. I honestly don't think you'll find any more accuracy from another mouse than the G500.
If you have been convinced to turn your mouse sensitivity all the way to the left to play games, you might want to rethink that practice and test it with a normal setting. I bet you cannot see a difference. I keep hearing people swear that it helps, and others say otherwise. All I can say is I see 0 difference in smoothness and tracking and that is with a 120hz monitor.
I personally have tried a lot of mice, and have been very happy with the G700, which surprised me, as it is wireless.
There is an article on the front page that mentioned the G9x as one highly rated.