Good question.
I'd use the Dream Play tape. I just pulled it out of the upstairs cabinet. I'll begin playing with it this week--as soon as I can think of something to learn. I don't know what it could be now. I easily learn whatever I want to learn as it is.
Back a few years ago I bought a piano. I would use the New Behavior Generator for learning pieces after my teacher played them for me. Worked great. The most amazing aspect of that adventure was discovering that whenever I dreamed playing a particular piece it would be committed to memory. Not having to look a the sheet music freed me to master the piece and get into its emotion. I quit playing the piano, because I simply ran out of time. There are only so many hours in a day.