Dude, I highly recommend the G-15 from Logitech, paired with the G-5 mouse (from same).
I bought them both about 2-3 weeks ago and man, it's changed the whole experience for me. The build quility for both is just outright fantastic, with a material feel not unlike what you'd enjoy caressing the dash of a new beamer!
Yes, I'm a big fan of Logitech, now more than ever. I was open to all others as well, but compared to my old mouse and keyboard (both Logitech), the G-15 and G-5 are a class unto themselves.
Both are wired, and I know you stated a preference for wireless, but lag IS more important to me than anything else, plus it's not like I'm going to be playing it away from my desk, so why even bother I say.
Peace,
HarryLemon