Very nice. I'm really impressed. You mention PCB below... can you take any pictures?
As for the buttons and so forth, I really havn't made up my mind WHAT I want to put, but I will hit you up when the time comes! At the moment, I am wanting my Amplifier, and any other normal switch to be controled by a Basic Stamp, and so I won't need to do any switches, but your solution looks soo damned good, I might go with that for the amp. I really like it.
I am interested in the USB coin holder unit... can you take pictures from below?