There may be technical issues, but from what I can tell it is a
religious issue for AIX vs Linux.  Both are good solutions.  Even a well
configured Windows solutions works, but it is not my preferred solution.

IMHO, a best fit solution for TSM is probably an AIX solution.  But if
you have no AIX experience on staff, and do have solid Linux people
available, then there is a reason for Linux in your environment.

If you are primarily a LINUX shop (or going to be), then going to LINUX
makes sense to me. 

As always, YMMV.
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