I've used the Sonnet SXS reader without any issues except that thunderbolt cables can sometimes come loose, which is not a problem with the actual reader but Tunderbolt's physical connection. It is important to note, however, that you will often be bottlenecked at drive speed. If I'm not mistaken, there is not much of a speed advantage when transferring to drives 7200 RPM or slower, when using Thunderbolt over USB 3.0. If you are transferring to solid state drives, however, there is a difference.