I have 6 boards with Raid on them and do not use them. I simply use those removable trays and Ghost, then once a week I ghost everthing to the backup drive. If you stick strickly to the same size and type of hard drives, (Two alike) then you can just duplicate your existing drive to the second drive. dis-engage the second drive (I use the electronic keyswitch type removable trays) and you have a backup that can be activated by switching the jumper.
Note: Win XP will not let you ghost to a different size drive and still be bootable, but it will work on the same type and size drive that you originally register XP with.