The Corsair Katar seems small, 85g and 111x64x38mm but the reviewer at Hardware Canucks did not seem to find it uncomfortable.  The sensor matches up to the competition, adjustable between 100 to 8000 DPI but you can see all of the buttons in the picture below, there are only 4.  However for many games, such as DOTA that may well be all the buttons you need and the simple design makes it easy to use in either hand.  At under $40 it is not overly expensive to pick up.  Check out the full review to see if this mouse is good enough you want it to fall into your hands.

"Can a peripheral that's endorsed by "professional gamers" be worthwhile? Typically no, but Corsair's Katar begs to differ. It offers everything FPS gamers could possibly want in a gaming mouse."

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