I have now been using the OWC Thunderbay4 mini. It is working really well with my 4 SSD drives installed in it. This is a replacement for the Promise Pegasus J4 which was no longer working properly. What is interesting is that when benchmarking my SSD drives in the OWC enclosure I logged Read and Write speeds right around 380MB/s. In the Pegasus I usually got Read speeds around 520 MB/s. OWC told me that the chipset in their drive limits each drive to a max of 400 MB/s...so that my performance was right on. I guess they do this to prevent over saturating the Thunderbolt bus...since 4 drives in there functioning as JBOD, each with their own "lane" could pump out a total of 1600MB/s [400MB/s times 4 drives]. This 400MB/s with SSD via thunderbolt as JBOD's seems to be standard as I got a similar answer from Rick at Macgurus.
Kind of interesting and thought I would share since at first I was concerned that my new OWC was operating a bit slower than the Pegasus J4. But of course the Pegasus wasn't working right in a number of other ways and the thunder bay 4mini so far after 2 weeks is silent...and rock solid.
Thunderbolt SSD speed limitations
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