I would have to recommend the good ol' ZBoard. I love this thing so much, I got one for each of my computers. The cool thing about it is the fact that you can change different key sets for different games (I have pre-ordered a World of Warcraft one). The only problem I can see you having with it is the split spacebar, but it only took me about a day or two to get to the point where I didn't notice it at all. Another big implecation would have to be the price.
In my opinion, it would definatly have to be one of the best gaming keyboards out there.
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