The StarTech Thunderbolt Dual SSD Enclosure S252SMTB3 is fairly expensive at just over $200 empty but thankfully they included a Thunderbolt cable; you will need to provide the second cable if you intend to daisy chain devices.  This model uses the first generation 10Gbps interface and allows you to install two SSDs in either RAID 0 or RAID 1.  In RAID 1 the drives performed as you would expect with the reads hitting close to theoretical maximum and write sitting just below half of that speed.  In RAID 0 the reads and writes on the 128 GB Corsair Force GS SSDs used by Bjorn3D for testing hit their maximum theoretical speeds; it will be very interesting to see the results of faster SSDs on a new 20Gbps model of enclosure.  If you want external storage that is as fast as your internal drives then this is worth looking at.

"Even though it is popular to use a network attached storage sometimes it is nice to have storage closer to the computer, for example for Timemachine backup on a Mac or just as a way to add more storage space on a laptop with a small SSD. The Startech enclosure we are reviewing today, the StarTech Thunderbolt Dual SSD Enclosure S252SMTB3, comes with a Thunderbolt interface that not only lets you daisy-chain it with several other peripherals but also offers a lot of bandwidth making it a perfect option for increasing the storage space on a Mac Book Air or other computer with little initial storage. After testing it turns out that it performs just as well as expected with just a few minor complaints."

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