Hi there,
I have no access synth but I want to buy one in the near future, but what is better playing on stage.
TI-Desktop or TI-Snow? 
I got a Clavia NordStage 76 ("Master"-Keyboard) and I do not use any computer on stage.
It seems Snow has not enough buttons, I have only one hand to modify the sounds while playing,
I cant read the display on dark or very bright stages, but I like the size the most of the snow, very handy!
Maybe there is also a sound difference because of polyphony, I guess this is not so important in a live situation.
PS: I play only live, no studio, no cd recording.
Thanx, for helping me to make my decision.
Kurt