Seems likely to take up the top spot for the best mouse I've used. It's very comfortable (but I suppose that differs from person to person) and has a nice rubberised surface. The buttons are very precise and well positioned, and there are plenty of them.
My previous mice for comparison: Razer Oroborus Razer Mamba 2012 Microsoft Sidewinder X8
Not a huge deal but the lighting is a little dull looking on some colours, however the colour changing ability is not why I purchased the mouse.