good reply..
then let me see if with your monster PC are able to setup one simple system setup and make live gigs as one standard keyboard.
let me soo how you play some audio-midi players, play styles and the all sounds over it.

just a simple ready setup system like you have to play one simple arranger-synth keyboard.
then make a simple video demo ( i dont care about the sound quality) and show us how you can play all and if the most time of your hands/finger are over the keyboard or always to use the mouse/PC keyboard...
http://www.youtube.com/watch?v=AlADLhdqffE http://www.youtube.com/watch?v=1ooKPAGhLeg

have fun