Scott, I'd use it like you do except I don't know if I need one assigned for Sustain.

The Midi Solutions controller is $129. I don't know how much your four button foot pedal is.

Maybe I could get three to work with one Midi Solutions controller and then a dual footpedal along with my single footpedal.

Maybe I should just get another foot switch and work with two pedals awhile and see how that goes. I'd say top two for me would be Vocal Harmony and either Auto Fill-In or the Variations (Fills), A-B-C-D.

For the A-B-C-D, does it just advance from A to B and then to C or can you go back and forth between, say, A and C?