Not going to lie, I'm a big fan of hard drive docks. Having something I can simply plug naked drives (2.5" or 3.5") into for copying files, making bootable clones, etc without having to deal with a bunch of individual enclosures is great. Even though I love my 2013 Mac Pro so far, the form factor also means you're going to have to be using lots of external storage. I recently came across one thunderbolt dock solution that I thought I'd give a try: the HighPoint RocketStor. It is a dual-drive (accepts 2.5" or 3.5") hard drive dock that connects to the computer via a single thunderbolt (thunderbolt 1) connection. I picked up one of these guys for music recording. I bought two SSD drives to use with it. Samsung 840 SSDs have been on sale lately, so I picked up a 120gb version (for storage of audio samples) and a 500gb version (for storage of audio files during recording). Both drives mounted like they should in the dock, the dock turns on when the computer turns on, and the dock turns off when the computer turns off. Using the Blackmagic disk speed test, I'm getting ~500mb/s read/write times from both drives out of the dock with a 5gb stress test. Looks perfect for my needs....so far, so good.
Pros:
Works exactly like it should
Cons:
Expensive compared to USB 3 docks
Feels a little cheap and plasticky
Only one single thunderbolt port (must be plugged in at the end of a thunderbolt chain)
I bought my dock here. Hard drives here and here.
Disclaimer: I am no way endorsed by any of the companies or websites mentioned in this post. All equipment was purchased by myself and I did not receive any compensation for writing this post.