The $79 OWC Envoy Express is the first diskless external Thunderbolt 3 enclosure and I got mine today! I’ve been using a Sabrent Rocket 1TB NVMe PCI M.2 2280 SSD in a $25 generic USB 3.0 enclosure. It has worked well but it is considerably slower than the internal SSD on my 2018 MacBook Pro (MacBookPro15,2 model indentifier). I’d like to use the SSD as a primary drive for video editing, so I wondered whether the Thunderbolt 3 interface would make a significant improvement. TLDR, it does… mostly.
You get everything you need in the box: the enclosure, a clip with self-adhesive backing that the enclosure slides into and a small Phillips screwdriver. The short Thunderbolt cable is captive, though it actually plugs into the circuit board so one could presumably replace it with a longer cable if needed.
The SSD itself just slots into the M.2 socket and is screwed down to hold it flush with the circuit board. The metal enclosure has a thermal pad that makes contact with the built-in head spreader on the SSD. In use, the enclosure did not get above 102-degrees Fahrenheit (39-degrees Celcius).
I used Blackmagic Disk Speed Test and AmorphousDiskMark for testing. I used the default options, which means that Blackmagic Disk Speed Test used 1GB as the test file size, and AmorphousDiskMark did five passes for each test with 1GB file size. The internal SSD and the external SSD are both about half full.
External USB 3.0 Enclosure
External Thunderbolt 3 Enclosure
According to the data, the OWC Envoy Express Thunderbolt 3 External Enclosure wipes the floor with the USB 3.0 enclosure and is on par or better than the internal SSD. Unfortunately, this isn’t quite the whole story; I found that the results using Blackmagic Disk Speed Test had variability between successive runs, infrequently to a significant degree (as in half the speed!) This was the case with both the USB and the Thunderbolt enclosure. I’m inclined to think that this might be due to the SSD drive itself. The internal SSD shows very little variability.
My provisional conclusion though is that overall, the Thunderbolt 3 connected SSD does perform significantly better than the USB 3.0 connected SSD, particularly for read performance.