I was thinking this might be better employed on an electric guitar. It comes with a piezo acoustic pickup and the preamp has a very high input impedance so it should work with magnetic pickups (or I can make it work). I'm already working on some serious onboard electronics for my ST-1L, including low-latency bluetooth, and on-board MP3 player for backing tracks, but if these things are any good, they could save an awful lot of work, and it would look damned impressive :-)
Has anybody actually used one of these? If not I might take a punt on one.