The Thunderbay 4 Mini RAID-5 edition is available with SSDs in capacities from 1TB to 40TB. MPG strong recommends the RAID edition.
Thunderbay 4 Mini configurations (non RAID) are also available, as well as hard drive configurations are also available.
Added to my review of the OWC 40TB Thunderbay 4 Mini SSD is additional analysis of RAID-4 vs RAID-5 with the OWC 40TB SSD.
As shown below, RAID-4 mode is the unequivocal winner over RAID-5 for read performance (blue vs green lines).
a> disktester run-sequential-suite -s 32 -3 512M --iterations 5 --test-size 4G
Figures are in MiB/sec. Multiply by 1.048576 for MB/sec.