I play a lot of FPS games such as older CoD games, Heroes and Generals an Red Orchestra, I've been doing most of that on my poker II with MX Blues. I have the granite set. However, I as aicrono have a hard time to find my way around during the keyboard with that profile. Also they seem to strain my hands a bit more than the DCS profile the OEM keys and the Miami set I use on it.
Recently acquired a Model M, will try that soon, I suspect it being just fine. Typing is great on it so I suspect gaming will be as well.
I had a Filco Zero with white ALPS clones once and gamed on that fine as well.
MX Blacks are not for me though, I don't like the feel of them.