I have a Razer Mamba 2012 and its an excellent wireless mouse (once you've updated the drivers to the latest versions). Battery's last quite a long while and even if they do run out mid-game you can plug the wire in temporarily to continue gaming until its charged . It's also very comfortable and looks the part too.
I had a Razr deathadder for a couple of years and it worked perfectly but was pretty basic. I didn't want the amount of buttons on the Naga however and gave Logitech a spin. I wouldn't live without the scroll wheel release now however.