I despair the answers that say "I ain't had no problem, what's the problem, there solved"

I've had no problems with CD-r's but then I haven't had a burner for 10 years and those CD-r's are getting cheaper by the minute. But if you are looking for a cast iron rock solid everlasting medium the internet via an ISP and webspace with a knowledgeable company is most likely the best option for long term sorage.

Terry Allen Hall - what archive medium have you got? double-up and triple might be a good policy. Or know your brands (if you can get the info) or use gold for the really important stuff. Your customers are not the problem - your precious archive is.
Ignorance is bliss. Enjoy.