I have a Logitech G5 and it's nice, but my only real gripe about it is the scroll wheel....
I hate how every middle click usually results in a roll instead of a click due to how the wheel can be tiled left and right (especially annoying with internet browsers where it's used to open links in new tabs).
Speaking of tilting the wheel, it doesn't register for Windows and I've never had it work even with the setpoint software. However, it does work on Macintosh computers which is great for design and editing software.
I also hate how it rolls, the clicks don't feel right and over scrolling happens all the time in a game like Counter-Strike.
Lastly, the rounded edge of the wheel feels too narrow and after some middle clicking, it usually starts to hurt the tip of my finger.
