Donny,
Perhaps Dan can jump in here and provide accurate info but as I understand things vArranger works best with the Ketron SD2 or similar unit which is what I use. I have tried pedals but prefer just scrolling with my finger - works ok for me especially on the iPad. The trick is to spend the time to do the controller button and slider setups which is easily done right in vArranger. Even a midi dummie like me can do it. Yes, the Roland A-800 Pro controller is a first class piece of equipment - key bed feel is very good too.

Deane