I've been using it for about two months now, and I haven't had the right-click-double-click yet. I've owned 2 G502 Proteus mice that both have had the problem. I'm hoping it's fixed with this Hero model. Otherwise it's the perfect mouse for me.
I know that the right-click-double-click is a well-known issue but its actually fixable. For me, I opened up the mouse and took out the actual button and opened it up and bent the clicking metal in the opposite direction to give it tension. The reason it double clicks is there's a mechanism that requires a thin metal plate to have tension and make contact with another piece of metal to complete the circuit thus giving the signal that a click has occurred. The double click occurs when there's not enough tension in the plate.