I purchased the GoFlex Desk 3TB a while back, when I bought the retina MacBook Pro, but I only went with the USB 3 version. The retina MacBook Pro had some USB 3 hiccups (now resolved for me) and so I never was happy with the USB 3 connection. It was quicker than USB 2, but wasn’t all that impressive. Luckily this drive can be swapped out for a Thunderbolt connector, and I purchased that a few days back.
Thunderbolt is fast, like move 5GB in “less than a minute” fast — and that’s to a spinning platter drive, not an SSD. It’s really expensive to go with Thunderbolt drives right now, which is why I only have one, but it is the future and makes a huge difference given that I keep my iTunes library and photo archives on the drive.
I highly recommend this.
There’s also a portable version, but I haven’t tried it so I can’t speak to its quality.