IBM 40/80 GB DLT - Manual (Page 39)

Tape drive failures are often caused by contamination in the tape path or by using
poor quality media.
IBM has very high quality standards for its storage tape and prices it accordingly.
To be able to support tape products, IBM needs to constantly test and evaluate.
However, IBM does not test and evaluate non-IBM products on an ongoing basis.
IBM cannot support any product it does not test. IBM can only support tapes
sold by IBM. If IBM service personnel analysis indicates a problem with
non-IBM media, including cleaning cartridges, it might be necessary for the
customer to replace the suspect media or cleaning cartridge with the supported
media or cleaning cartridge. When you need to restore data from tape, you need
to know that you can count on it being readable. Any savings incurred by using
low cost tape is of no value when you cannot access the data reliably.
Part 2: Appendixes 2-5