Quote from mercurial:
I guess it would require more keys for stock trading if you take in to consideration all of the order routing options.
I've used XKeys for 2+ years for stock trading...wouldn't want to trade without one now. Also if you need more keys they sell bigger keypads.
The pic in the link is from when I was trading the Cyber. The keys are all different now.
http://www.iwinfree.com/xkey.htm