I keep seeing rave reviews, about this mouse, at various hardware sites. I simply can't believe any of these reviewers actually used the mouse. This is the worst mouse I've ever seen: I set it up on three computers at two different locations and I got the same result on every one of them - the mouse lags like crazy. If you stop moving this mouse for any length of time (like sitting and reading an article) it hibernates....then when you move it, it takes up to a second to wake up. This same problem affects the scroll wheel so, the mouse arbitrarily skips "clicks" when moving the wheel. I returned this mouse to the store within 24 hours of buying it. Do yourself a favor and buy a MS optical mouse WITH A CORD. They are wonderful.