I have a G5 and it's holding up rather well. Even my old MX700, which got some really heavy usage, still works fine to this day. The charger has given me a fit a couple of times (common problem) but it still charges the mouse, and the only real sign of wear I've noticed on the mouse is that the scroll wheel has a bit less tension than it used to. It's not loose or anything though, and I actually prefer a bit less tension than my G5 has (when clicking the button downward, not scrolling) so the MX700 was really like a pair of shoes. The more I used it, the more comfortable it got. It's just now in its prime but I got tired of charging it, so that's why I use the G5. 🙂