Summary: Love the design of this mouse! It fits comfortably in the hand, and the fat, rubbery scroll wheel feels just right. It's not noisy (click-y) and feels good on the finger tip. I'm subtracting one star because the software for this model omits a cool option that I loved on my old Gigabyte M6800: there is no longer a programmable quick-menu option.
Summary: This is my second time buying this mouse; not because it broke. A few years ago I gave away this mouse to a friend when I got a new gaming mouse. Now I'm switching back to this mouse because it's better for fps games. When gigabyte says that it's for fps games, they were not kidding. The only con of this mouse is that if you were to using it for switching weapons with the wheel, you would have a difficult time.
Summary: This was an upgrade for me, and I'm liking it a LOT - been using it heavily for MMORPG games (not shooters) for several months now and the performance is flawless. It did take a week or so for me to get used to the thumb groove (it actually hurt my thumb for awhile - I'm just not used to having anything touching that surface - I've used Microsoft Intellimouse opticals for nearly a decade now) I would recommend this all day long to just about anyone.
Summary: Maybe I got a dud, but the mouse is varying degrees of inaccurate. I tried changing the settings in the clumsy software that comes with it, I tried Windows' own Mouse settings. Different mousepads and surfaces. The cursor sometimes twitches even when it's holding still! And now after a year of using it, it occasionally stops responding and I have to plug it back in. And the mouse is starting to spasm out of control on occasion.
Summary: It's a good mouse, but it takes some getting used to. I like it for gaming and it does well for casual computing. It's comfortable, accurate, the adjustable DPI is nice, very useful. It looks pretty good, too. Great deal for the price ($30).
Summary: I used this mouse with a steelseries qck thick, and I eventually gave this mouse to my mom, who is still using it without a problem. It is an excellent mouse for the price. Highly recommended buy.
Pros: inexpensive, decent build quality, good sensor