At the end of January I had called out my excellent experience with an external Thunderbolt disk http://goo.gl/S9j52 .
In the interest of full disclosure, I should add that after 2 months the drive died. Somewhat strangely: not accessible via Thunderbolt, but via USB. Reformatted, Thunderbolt worked, then became extremely slow (factor 100), USB as well, reformatted on a Windows machine, improved initially, then extremely slow again. ???
Whatever, there was an excellent return experience with Amazon, and I have a full refund. Am wondering what to do now: buy again? In the meantime I have acquired a drive dock – a piece where you insert raw disks (SATA), it's attached to my computer USB(3); needs a separate power supply. Inconvenient, but much cheaper, and popping in raw drives may be a solution for a while.