MOD/DVD-RAM (similar technology) is very good for smaller backups
with high reliability requirements. Also for long-term storage.

Indeed - I use MO for just that reason, however now also use DVD-RAM:
o MO media QC has blips - a few too many
---- Sony 540MB 3.5" -- block errors on new disks
---- Fujitsu own 3.5" -- block error on *same place* on every disk - factory format
error
o DVD-RAM has been ok - and is higher capacity
---- £ 10 will get a two-sided 9.4GB disk
---- LG-4082B will write to them once removed from the caddy

Since I use DVD-RAM once-only for archive the removal from the caddy is minor.
If bothered use cotton gloves - whatever - it's 15x MO capacity for the same price.

MO is best for the most critical backups
o It was designed for data reliability from the ground up like DLT
o It is not a converted audio standard like helical scan DAT, or DVD

However, the "real" MO systems are based around the 5.25" form-factor:
o New blue-laser ones offer a migration path to very high data capacities
o The 5.25" form factor is relatively well proven in medical/mil/industrial

For the most part, DVD-RAM offers a good half-way house:
o Reliability is good - it is Phase-Change unlike DVD+/-R & has better error correction
o Drives are cheap - so having 2 different branded drives isn't impossible (or suppliers
:-)
o Disks are cheap - 9.4GB can be had for just £6.99, sealed, a bit more elsewhere

MO is ~£200 drive & ~£10 media for 1.3GB v ~£60 drive & ~7 media for 9.4GB.
Critical stuff is best on MO, but with those media errors I think it's forget about
decades:
o Yes, backup media can last a long time - DVD-RAM probably, MO most probably
o However, it is perhaps more economic to keep changing technology every few yrs
---- because technology will offer more capacity, perhaps more reliability for less cost
---- that is particularly so with media cost as archives grow - eg, DVD-RAM v MO

Agreed - many people backup to DVD-RAM or HDs "incorrectly"
o They simply drag-n-drop files - directory is there, so it must be ok
o Better to use a proper backup tool - that actually does a proper compare
---- altho even XCOPY can be forced to do a verification as I recall
---- on DVD-RAM that might be an exercise in s-l-o-w-n-e-s-s however

If HDs are used, I prefer a "micro-PC" converted to NAS - with a few scripts to check
the data integrity progressively to another identical machine working in parallel. That
need not be particularly expensive - Mini-ITX snails don't cost much, recycle some of
the older 1U PSUs, make/re-use a case, whatever. Match solution to data criticality.
--
Dorothy Bradbury