Daniel Feenburg at NBER writes a good review comparing performance, reliability, price, and other aspects of common RAID NAS solutions. Among those covered are Netapp, DNF, Excel-Meridian, and Linux white-box with RedHat Linux and promise IDE controller.

What makes this version somewhat unique is it deals with the problem of secondary unrecoverable bit-errors that were previously undetected but manifest themselves when you go to rebuild a failed drive. This problem is more common than one would hope, and it is explained well.