As the question was put to Sen Dole on whether he wore boxer shorts
or briefs he answered "depends".  It depends on whether or not you will
ever need to access tapes from the other server, or whether or not you
want to go to the extra expense, or as somebody has already mentioned
whether or not you need multiple drive access which is very handy
during reclamation.  The method oh how you are managing your tapes
may get more complicated if you have two separate libraries.  Do you
use a Tage Mgt system or is it manual.  How about tape numbering? etc
etc .