Luckily, as you may know, CM is pushing their new stuff pretty hard right now. I will have a chance with the MM530 soon and hopefully it might deliver better experience for me. A good start would be non squishy FW and back buttons on the side, like in the unfortunate case of the Revenger S.
IMO the mold of the Mamba tournament is Nirvana. Moving my hand from any mouse after extended use to the Mamba is like the feeling of taking off your shoes after a long day of work.
I didn't have any firmware related issues during the testing tession with the MM530, but I had some errors popping up while I was testing the Revenger S (mostly when I was starting up the driver program it somehow didn't recognize the mouse/crashed). Huge props to Cougar for listening to the users, I had many suggestions that they implemented later on (I guess I wasn't the only one suggesting these things), but they still need to work on some things. Btw the MM530 has pretty much the same quality (mushy, hard to press) side buttons as the Revenger S, so it won't be an upgrade that way.
As for the Mamba, I did not have the chance to try it yet, but I definitely will, if they care to release a reworked version with a proper optical sensor.
Looks like Cougar something
I guess you think of the Cougar Surpassion, and yes, they are similar, however they are not the same. And CM's design was first with the Alcor/Mizar back then.