After a few weeks in use, I have to say the Cougar 600M laser gaming mouse is very comfortable. It is more comfortable than the 700M, and perhaps more so than any other mouse that I can recall using. It fits my hand well, the texture allows me to get a good grip, the buttons are well laid out, and I find the feedback of the buttons to be just right. I can use it for hours on end without any discomfort, and overall it has a very natural feel to it.