Are these individual drives based on magnetic harddisks?
If so, why?
Don't you think you'll have archival needs beyond ~5 years?
Yes they are. I didn't know that there was any other kind except for new and outrageously expensive solid state drives (ala Mac Air).
These drives are rotated through and each update is verified.
From what I've read and heard, the likes of Schewe and Reichmann use only hard drives for permanent storage. I have also read in these forums and others about the problems of reading RW+ CDs and DVDs (dye based technology) that are not permanent either.
What are you using?