I purchased this M560 wireless mouse to replace my second Logitech Anywhere MX905 mouse that I use with my laptop. I tend to wear them out on the left button, wheel and scuff pads. While the M560 is about 10% larger than the MX905, I find it is easier to hold due to superior contouring, with a nice dimpled grip; though the rubberized material is not as soft as the MX series. In fact, the M560 is a bit too much plastic for my liking, as compared to the premium feel of the MX905, but it has proven to me to be a mouse that gets the job done in the same manner as the MX905; minus the Darkfield laser diode. As with all Logitech mice of this calibre, all of the buttons are programmable to any configuration that suits – assuming you have bothered to install the Logitech Setpoint software. I have reprogrammed the thumb buttons to match what I had with the MX905, as I like the ability to quickly move forward and backwards through web pages, etc. The M560 only requires one battery, while the MX905 had two, but so far the M560 is consistent in its miserly consumption; although I haven't had it long enough to compare to that of the MX905. And to top it off nicely, the M560 comes with the same Nano-receiver as the older mouse, so that never leaves the laptop if I move around the house.

The wheel on the mouse has no “damper” on its movement, when I scroll with the wheel then move my finger to click, the wheel rolls back, or when I sweep the mouse across the mat, the wheel moves, which means the thing I was about to click on, e.g. A cell in a spreadsheet or in fact this text box! has moved from under the pointer, or the image I was zooming in on, with the wheel, suddenly shrinks out of view. Also, @MightyApe, p-l-e-a-s-e make it quite clear in your specs the size of the mouse, this mouse is in fact a medium, which means it's too small for my hand.

Very good mouse. Very comfortable