I've been going through this the last couple days, trying to figure out what works best for our N3. Yesterday, I went to Fry's and purchased a handful of their cheapest flash drives ($4.99 each), which were a little Kingston 4GB drive. I've been having issues with some files not working. In any event, here is how I organized these drives:
- dedicated drives for each composer, with nothing on the drive but ~99 .midi files (downloaded from http://www.piano-midi.de/midi_files.htm
if anyone cares)
- no subfolders, no other files, etc. (even though subfolders do work)
- renamed files to be less than 8 characters (silly, but it seems to work), plus the extension
So far, it seems to work very well. My wife was not thrilled about buying the AvantGrand N3 after we sold our old Steinway M project piano (think rusty old Camaro in the front yard, covered by blankets, and needing work). In any event, this has become her favorite feature with the N3. Very good stuff.
I'm still searching for a "midi radio" solution for the N3, short of a $1k+ Yamaha Disklavier solution. If anyone has any great ideas... I'd love to hear them.