I'm thinking of using my christmas money this year to invest in a RAID 1 system. (Think, two hard drives acting as one, so if one goes out you still have a copy of your drive.) However I'm also thinking of setting up a secondary RAID system for backup (In case of Virus despite the fact I'm on a mac, human error, or corruption). However do I really need a secondary raid system for my backup or would i be just as good having a single hard drive.