With its constant 800 dpi of sensitivity, mouse movement is smooth, very accurate, and comfortable. In the real world, this mouse lives up to its promises, delivering what a mouse should: effortless navigation. I have been using this mouse for about one and a half years and I can say this is the best mouse I have ever used. Whenever I am away from my computer, I really miss this mouse.
In the browser, the quick scrolling, back and forward buttons are a great combination for effortless navigation. In Photoshop or other photo editing tools, the mouse allows for full control over brushes and touchups. For gaming, the many buttons give quick access to many commands and actions giving you an edge to your game whether you are playing a first person shooter or an RTS.
The wireless functionality is great for freeing up precious desktop space and giving more freedom to use the mouse anywhere (and I mean anywhere, the wireless tracks beyond the base station's room).
The battery life on this mouse is excellent. On a full charge, I can expect about 7 days of regular use (several hours at my computer). On the top of the mouse is a battery level indicator with 3 bars. Personally I have never dropped below one because I just have a habit of charging it every couple of days. The SetPoint software gives a more accurate estimate in days and percentages to help gauge battery life.