I work for a large hospital. I have been asked to investigate
possible configurations for archiving something between a few
hundred terabytes and a petabyte of data for 25 years. This would
be clinical records that we need to keep in case of a malpractice
suit. The retention period is 25 years because there are two ways
we can get sued for alleged malpractice involving a pediatric
patient. The parents or guardians have a seven year window of
opportunity to file suit, starting at the time of the alleged
malpractice. The patient has a seven year window of opportunity,
starting at his or her 18th birthday. In principle, the retention
period should vary depending on patient age, but nobody I have
talked to so far thinks it is practical to sort records in this
way; they want a uniform retention period that covers the worst
case scenario (a patient allegedly harmed as a newborn suing just
before the end of his or her seven year window).

As far as I can tell, the most expensive part of such a
configuration is the media, and LTO media will cost about a third
as much as the most economical MagStar media (extended length 3592
volumes read and written with TS1130 drives). With the sort of
workload described above I don't expect any difficulty staying
within the recommended limit on the number of times an LTO volume
passes over the tape heads. Are there any other reasons to be
nervous about using LTO for long term archives?