The Gigabyte M6800 has optical 800 or 1600 dpi sensor (switchable with a button). It has 6 programmable buttons (left, right, middle, two thumb buttons, and the dpi button).
Ranked in these QuestionsQuestion Ranking
Pro Good tracking
It is accurate and responsive.
With tracking and comfort offered this prices is amazingly cheap at $15.
Pro Good for palm grips
High arch and sculpted form make it very comfortable for adult hands.