I've always used Logitech mice and probably will do so forever
Random Mouseman -> Mouseman Dual Optical -> MX 900 -> MX 1000 -> MX Revolution
The MX Revolution is by far the best one, yet. The batteries last days (even after 2 years), it's heavy and big enough for my big hands
Although the
Roccat Kone would be quite a competitor, at least the test results where pretty good for a new manufacturer.