Downside of such complicated mice with fancy circuit boards is that you can have issues like my s2 had, where the thumb button got stuck. This somehow caused a software lock, rendering the rest of the mouse unoperational; a nice 90$ paperweight. I don't mistreat my electronics either, it was not dropped or anything like that. This sort of stuff should not happen on such an expensive mouse. Coincidentally it happened 2 months after the warranty expired.