Hands down all their best performances ever.
I have this mouse, the keys on the keypad took too much pressure for my taste. When playing a game, pressing one would often nudge my aim off the target. Also I never managed to get the DPI/speed settings to match the speed of my previous mouse. (Razor Naga) so aiming was harder to begin with, making it extra frustrating.
I replaced it with a Logitech, way nicer and only about 10 bucks more than this if you catch it at the right time on Amazon.