Pros: I've had this mouse for just over a year and have loved it. It has been a good mouse that I feel is worth it for the price. Battery life was good in my opinion, I never manually shut it off, but batteries would last 3-4 months with heavy use. I felt the responsiveness was very good. (Not that great on glass like they clam) It was small so it would easily go with me when I took my laptop.

Cons: I'll start with the things I noticed after a little bit of use. While the size is great for travel, after prolonged use I felt my wrist and fingers would get fatigued. The next thing is using it on glass. I have a glass desk and that is the number 1 reason I chose this mouse over the others. Now it would work on glass but not very well. I would find it to be jerky or glitchy at times. But the reason I am writing this review is that after only about a year of ownership it the left click button has started to get glichy like others have stated. Not only was it getting harder to push but when you would go for a single click it would double click or when I would attempt to click and drag it would let go of the window. It has gotten very frustrating.

Overall Review: I still like the mouse and just bought the pro to replace it while I see if Logitech will back up their product for 3 years like they claim.