That G500S looks like my old G7, which I loved for about 8 years until it quit working. I currently have the G403, but I would think the G500S would be superior even though it's an older model.
Only thing I don't like about my G403 is that it only has 3 DPI settings (they are customizeable), but other mice I've owned had more. I can't find how many the G500S has.