I picked up a My Book Live Duo 8TB model and using it as RAID0 for maximum storage for File History in Windows 8. I also do regular full and incremental backups to a 4TB USB 3.0 drive. I also supliment my digital pictures and documents with backups to iDrive and SkyDrive. With that set, RAID0 is less scary. Plus, since it is for File History and backups mainly, I am not too concerned if I lose that data if the time comes to replace a drive.
I am thinking of getting another My Book Live Duo for storage/archiving, so I may set that one up as RAID1. Can you also set it up as JBODs (just two seperate drives)?