Within 6 months of using it the battery burst inside the mouse. It swole up so much the plastic inside the battery compartment cracked trying to get it out. Warranty gone - they weren't willing to listen. About the same time the rubberised black coating started coming away from the shell. I had a Razer Blackwidow keyboard doing the same thing so the issue seems to effect all their products with the rubberised finished. They've maybe fixed it now and use an alternative coating but too little too late. £250 wasted on what is supposed to be premium quality.
The thing with Razer is you're not paying all that money for the quality of the mouse or keyboard, rather the quality of the packaging it comes in. The Mamba arrives in a crystal like display box, it looks damn fine but in reality it's just a £40 mouse dressed up like a cheap tart
. Their software does suck badly too, I could only ever get it to work sometimes while gaming. The on the fly sensitivity was a no no for me. The Perixx Mouse I'm using now is so much better. It cost me £25 lol
It is fair to to say 'Razer - built by chancers for gamers'