Pros: I found it very responsive (1000 dpi). Liked having a separate programmable button on the side. Scrolling worked well. This mouse would be perfect for me except for the wheel button issue (see Con).
Cons: In Firefox, I use the wheel button to open links in new tabs and to close them. The wheel button on this mouse doesn't seem to always trigger an event, even after multiple clicks. This appears to be a common issue.
Cons: It's heavy, which is ok for mice that fit your hand well. The middle button is difficult to click even when using your index finger The extra buttons are useless and cannot be reassigned to something of use.
Excerpt: If looking for a cheap mouse with find quality, there are much better mouses than the Microsoft Comfort Optical Mouse 3000. Not only does the “special” and unique functions it has are difficult to use, but it is very overpriced for a mouse at this standard. I’ve bought another mouse already to replace the Microsoft Comfort Optical Mouse 3000 to overcome the stress of using the Microsoft Comfort Optical Mouse 3000.