I can only agree with the positive reviews. I have the Mouse now 5 months, and it is working properly. Now, after about 5 months, the first set of batteries is empty. I use the Mouse lancer. Thus, if 5 days a week used. At night and on weekends I turn off the mouse. Very good, I find that the LED starts to flash when the batteries are empty. You can still use the mouse for about 3 days. So plenty of time to look for new ones.