I gotta agree with Caye on this one. *ducks*
It really doesn't matter too much what keyboard you own or use. As long as it doesn't suffer from ghosting/keylock, you will be fine. I can see how those used to playing with "low profile" keyboards might need an adjustment period after buying a mechanical, but overall I feel as though they would prefer a mechanical over something with membrane switches for gaming and not. I actually like the travel distance on my spacebar, although some people might say that it's too far. (Mechanicals are also just more of a pleasure to use in general due to the feel and the sound. I feel like I can type faster on a mechanical because you feel every single keystroke..) Before I got my fancy schmancy gaming keyboard, I was using a $2 thrift store Dell PS2 keyboard with membranes for YEARS. I also had a super old PC and positively ancient monitor which only supported an 800x600 resolution, and yet I still managed to be very competitive. It's not really what you have so much as what you're used to. My Corsair kb is USB rather than PS2 and I feel no latency whatsoever.
I don't think that there's any definitive "best" keyboard for Worms because I am sure that if we looked at video footage of our hands and the hands of other players, we would see that we all do it a bit differently. Just pick a keyboard and stick with it. Eventually your muscle memory is going to adapt.
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