I don't think that the iTunes model is going to work.  I think that the music industry is going to have to shift to a subscription-based system much like the film business. 

That said, I think the better way for David to go would be to offer a subscription service to his new demo recordings.   If DB wants to protect the distribution of his music, he might set up a listen-only website.  If he doesn't care about letting fans have the mp3 files, then perhaps a subscription service which involves mailing a CD periodically might be the better alternative.

Just my two cents.