I recently purchased a pair of 1TB Western Digital WD1002FBYS RE3 drives for use in an external RAID enclosure. I have found that they tend to drop out of the array after a while. Thinking it was the enclosure I tried them on another one but found the same issue. So a bit of googling and I found http://www.tomshardware.com/forum/251076-32-raid-issues-western-digital-hard-disk which suggests that: "WD's "RE" (RAID Edition) HDDs support Time-Limited Error Recovery ("TLER" ): http://www.wdc.com/en/products/productcatalog.asp?language=en As a non-TLER HDD fills up with data, the error detection firmware might take too long, and the RAID controller may drop that HDD from a RAID array." So now I wonder what SATA drives have firmware which is compatible with RAID arrays (esp. RAID 1, 5, but not 0)? I have not been able to come up with the magic set of keywords to ellicit the answer from Google. However, various sites suggest that Seagate & Hitachi are in general OK. Does anyone have any generic (or even specific) guidance on how to work out if a drive's firmware may harbour code that is potentially an issue in a RAID0 setting other than stating that it must be 'enterprise' ready?