Guys, guys, guys, trust me RAID
is not a backup system!!! You are fooling yourselves if you think it is. Don't just take it from me....(I do work in the computer data storage industry though ;) )
One of many Google links:
http://www.overclock.net/t/1254683/w...ackup-solution
I never mentioned backup to CD/DVD (BTW I have ripped CD's from 1997 that still play perfectly well ;) ) use another disk set preferably 2.
I will even go as far to say you maybe better off with a single high reliability drive for your music store and perform regular incremental backups to a second and third drive...like I do :)