The Razer Salmosa hasn't let me down through the weeks of abuse. The mouse worked flawlessly. The speeds manufactures advertise with which the mouse operates on and how fast it is, it's the same as car manufactures like Ferrari and Porsche keep telling their customers that they made their already fast car even a second faster. Will you actually feel or notice the difference? Does this mean the Salmosa with its optical sensor is less good than infrared sensor powered mice, or laser mice? No not necessarily.