Summary: I am using it with Windows 7 and I find it slow on scrolling up or down + at times the mouse will generate commands that you are not seeking for example occasionally when scrolling up or down a page it will produce various windows that are not requested.
Summary: Very jittey. The scroll function doesn't react quickly. The "mechanical" mouse MX anywhere is far better and more reactive. When scrolling quickly at the bottom of a page you cannot stop the scroll by pressing the mouse (like you would stop the wheels from turning on a "mechanical" mouse).
Summary: hardware is cheap, software clearly has issues... after a month of using it, it started to freeze. I had to reinstal the driver software several times, but continues to feeze. Very frustrating to pay so much for such a poor quality device. Will avoid Logitech products in the future.
Summary: I use Windows 7, Windows 8 and Mac OSX. I like the smoothness and the ease-of-use of the Apple Magic Mouse. The T620 is simply too annoying to use. In addition to jumpiness, it often launches a command which performs an ALT-TAB in place of a left click. Happens every 30 minutes or so ....
Summary: This is an interesting concept but the function is not there yet. I have had this product for about 5 or 6 months and find it is jumpy, too sinsitive at times and doesn't sense at others. I have limited some of the controls on it to help it stop jumping 5 pages when I am trying to scroll down one.
Summary: The biggest problem I have with this mouse is that when I want to left-click it will right-click and vice-versa. I guess it might have to do with the way that I rest my fingers on the surface, but it always seems like I have to click at least twice to get the proper response.
Summary: 1) product feels very cheap, 2) doesn't hold up in the hand, 3) navigation tool ok, 4) try to price itself as an alternative to apple mouse, clearly not. Logitech should focus on creating good product otherwise it will continue to be displaced by cheaper alternative.
Summary: Suffering significant RSI pain, so had to do something drastic as existing solution unacceptable. This looked like a good option, low touch, gesture driven (like a mac, i guess) and reassuringly expensive so seemed a low risk.