Collocation should be used when you have a business need for it.
Specifically, if someone comes to you and says "I must be able to restore
the data on this 20 GB disk in three hours or less."  Then you MIGHT need to
consider collocation.  Always be sure you can't do without it before you
decide to do with it.

Collocation is a wonderful feature.  However, it can be costly on a
day-to-day basis as typically many more tapes will be mounted during
migration.  It can also be rather tape inefficient.  We use it for very
specific data that doesn't collocate naturally and where the business need
drives us to it.

Kelly J. Lipp
Storage Solutions Specialists, Inc.
PO Box 51313
Colorado Springs CO 80949
719-531-5926
www.storsol.com
lipp AT storsol DOT com