Why not RAID 0 for performance?
RAID 0 stripes data across several disks. This results in very good read and write performance. However, failure of any 1 drive will lead to data loss. Instead of using RAID 0, we can setup a second RAID 1 drive, and split half of the accounts over to the second RAID 1 drive. This will distribute the disk IO over the 2 RAIDs, with good data redundancy.