I've been using the MX518 gaming mouse for about 15 years and I'm very happy with it. I had to replace it once during that time, but I was able to get the exact same model. I recently bought another one for my second computer, thinking it would be identical to the old model apart from a few minor cosmetic changes. As soon as I received the mouse, I could tell that it was a cheap copy of an old model. The old model feels nice and solid in the hand, and the new one feels like plastic garbage. The new one also makes a slight rattle when you pick it up and put it on the floor, while the old one doesn't. I have no complaints about the new model's features or performance, but it feels terrible in comparison.