On Sep 7, 2007, at 9:42 AM, John C Dury wrote:

...Any LTO-4 libraries more reliable than others? Do tapes last 5
years? ...

Tape life is limited by usage.  Manufacturers will quote various
number on archival lifetime (sitting on shelf; usually 30 years),
number of load/unload operations, and number of passes of the media
over the head.  See the Availability section in http://
www.storagetek.com/products/product_page48.html for an example.  An
HP Ultrium warranty statement (http://h20000.www2.hp.com/bizsupport/
TechSupport/Document.jsp?
locale=en_US&taskId=120&prodSeriesId=34648&prodTypeId=12169&objectID=lpg
50212) is "one million passes or 260 full back ups (FVB) or
combination of FVB and Restores (whichever is soonest)".  Also, see
article http://searchstorage.techtarget.com/tip/
0,289483,sid5_gci1253102,00.html on LTO lifespan for perspective.
Further, a given technology may quickly become obsolete, rather than
wear out: an LTO-4 cartridge finally taken off the shelf in 2037 will
be a knickknack rather than usable media.

   Richard Sims