Even my second model in which the middle mouse button (scroll wheel) after about 2 months gives up the ghost. The mouse is great, feels good in the hand, has many well-to-reach buttons. Only the wheel seems to be the Achilles' heel. Already my second G602 which is defective within a short time. The mouse no longer registered to click the middle mouse button.
I'm going to wait an exchange and report in a few months again, maybe I had bad luck and two mounting models caught. (But what really should not be)