i have used this after my misery with the razer mamba. It's WAY better. No complaints in any way, it's even too fast if you switch it all the way up. I can really reccomend this for people who want a stable, functional mouse.
"we couldn't even think of 15 commands used often enough to warrant mouse buttons of their own"
In competitive pvp in WOW for instance I have about 32 macros that I try to bind to my MOUSE in combination with ALT, CTRL and SHIFT (I remap SHIFT to F* with a free util). I always want MORE mouse buttons, not less. Sure it takes practice to learn how to use effectively -- but once you do you never want FEWER buttons... faulting hardware for affording more options than YOU want personally doesn't seem like a valid criticism.
M90 sucked software and onboard memory wise. M95 Corsair replaced it with for me is much better. After a few days of constant use you will get used to the thumb button layout but I still have trouble hitting the correct top row thumb buttons some of the time. Got a Logitech G600 to replace this on my desktop and it blows this away but I still use this with my laptop and it is a pretty good gaming mouse.