I have some thoughts, based on my office environment and research for my home system (still using a multi-disk backup system with manual implementation).
I passed on Drobo not because they fail —all drive will eventually fail — but because of the proprietary data write system. If it fails, only they — if anyone — can perform recovery.
Michael, FWIW, I had a long talk with a Drobo rep at PhotoExpo in October. She assured me that Drobo now offers a recovery service. Then again, she was in sales, not support…
I like RAID systems with hot-swappable drives. As long as a drive failure is quickly addressed — a replacement drive swapped in reasonably soon — the data is not at risk or only minimally so. That said, you still have to back up your data. Period.
Backups can be other drives (they are certainly cheap enough) or DVDs (that can become a lot of disks) or tape.
Jon Kandel A New York City Nikonian and Team Member Please visit my website and critique the images!