Hi Chris - you're absolutely right that CD and DVD discs vary enormously in quality and staying power. The band I used to be in made an album on CD some years ago - copies of which were burned using semi-domestic equipment. I dug one out recently and it played exactly like a very old, scratched 78rpm record - totally unplayable. There were no obvious degradations on the surface of the CD - it just sounded like crap.

To my simplistic mind, vinyl is actually one of the more stable media. I have discs going back nearly 50 years which have been looked after and which still sound great. My plan is to make mp3 copies for convenience (iPod, etc.), but never to get rid of the original vinyl like so many of my friends did when CDs first appeared on the market.

Failing vinyl, the only answer for safe preservation seems to be - as you say - plenty of duplication in the archiving process!