RAID 53 should really be called "RAID 03" because it is implemented as a striped (RAID level 0) array whose segments are RAID 3 arrays

RAID 53 has the same fault tolerance as RAID 3 as well as the same fault tolerance overhead

High data transfer rates are achieved thanks to its RAID 3 array segments

High I/O rates for small requests are achieved thanks to its RAID 0 striping

Maybe a good solution for sites who would have otherwise gone with RAID 3 but need some additional performance boost

Very expensive to implement

All disk spindles must be synchronized, which limits the choice of drives

Byte striping results in poor utilization of formatted capacity