This SSD runs like a race car but is built like a tank [Review]


Save time with super-fast OWC Envoy Pro SX portable Thunderbolt SSD
The fast and rugged OWC Envoy Pro SX is ready to go on the road.
Photo: OWC

The OWC Envoy Pro SX uses Thunderbolt to provide the super fast data transfers that professionals need. And it’s drop-proof and waterproof so it can stand up to real life.

I put the 2 terabyte external SSD through testing. I’m impressed.

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OWC Envoy Pro SX review

If you work with big files, waiting for them to copy from your Mac to an SSD gets old. And it’s a waste of your valuable time.

And once you have a day’s work — or a week’s — on an external drive, you don’t want to take the chance than a mishap will trash the drive. Something as simple as a coffee spill can be a disaster.

The OWC Envoy Pro SX can handle both. At up to 2847MBps, it’s about as fast as an external SSD can be. And it’s rugged so you don’t have to baby it.

Hardware and design

The Envoy Pro SX is very portable at 4.5 inches by 2.75 inches by 0.6 inches. And it’s surprisingly hefty for its size, coming in at just over half a pound.

You can definitely get smaller SSDs with the same capacity. But the extra bulk is armor. It can shrug off being dropped over 25 times at every angle from a height of four feet. And survive up to half an hour in a couple of feet of water.

There’s a single Thunderbolt port on one end. This is also how the SSD gets all the power it needs, as well as make data transfers

The aluminum casing of the Envoy Pro SX has fins to help it shed the heat that large data transfers can generate. It’s a design that works — I transferred about 300GB of data onto the drive as rapidly as possible and it never got above slightly warm.

The SSD currently available in capacities of 240GB, 480GB, 1TB and 2TB. Here’s hoping OWC eventually releases versions with additional capacity.

OWC Envoy Pro SX review
The OWC Envoy Pro SX can be used almost anywhere. You don’t have to coddle it.
Photo: Ed Hardy/Cult of Mac

Thunderbolt only

The most important fact about the OWC Envoy Pro SX is that it is Thunderbolt only. Apple is a big supporter of this standard and you’ll find Thunderbolt ports on all recent macOS desktops and laptops, and even the latest iPad Pro models. Many PCs have it too. And even a few Chromebooks.

But it won‘t work if you plug the SSD into an ordinary USB-C port. That’s true for computers that don’t have Thunderbolt, and for Mac accessories that turn Thunderbolt ports into USB-C ones.

The accessory comes with the necessary Thunderbolt cable. This is 25 inches long — plenty enough to be useful.

OWC Envoy Pro SX performance

OWC promises data transfers at up to 2847MBps. But sometimes companies hype theoretical top speeds when real-world performance is much less.

In testing the real-world Thunderbolt performance of the Envoy Pro SX, I copied a 10.5 GB file from my computer to the external SSD in 7.2 seconds. Transferring the same file from the OWC product to my computer took 10 seconds.

For comparison, that’s at least 50% faster real-world performance than transferring the 10.5GB file to/from a Kingston DataTraveler Max that uses USB 3.2 Gen 2, not Thunderbolt.

I had to use the 10.5GB file for testing because my usual 1GB test file transferred so quickly it was hard to get good measurements. It took less than a second going in either direction.

All in all, my real-world tests show the Envoy Pro SX is very, very fast, if perhaps not as quick as the theoretical maximum.

OWC Envoy Pro SX final thoughts

OWC Envoy Pro SX has a single Thunderbolt port for power and data.
Take note: The drive has a USB-C port but is Thunderbolt only.
Photo: Ed Hardy/Cult of Mac

This external SSD is easily rugged enough to take to a filming location or job site. And the OWC Envoy Pro SX is completely quiet so it won‘t draw attention if you use it for Time Machine backups instead.

Just make sure every computer you intend to use it with supports Thunderbolt.


The 240GB version of the OWC Envoy Pro SX is $179. The 480GB version is $229. Jump up to 1TB and the price rises to $299. The 2TB one costs $479. It’s available on either OWC’s website or Amazon.

Buy from: Amazon

Comparable products

Anyone considering the OWC Envoy Pro SX should also take a look at the OWC Envoy Pro FX. This is almost as fast, comes in the same rugged casing, and can be used with almost any device that supports USB.

Or there’s the Kingston DataTraveler Max. This is slower and not anywhere close to as rugged, but it’s smaller.

OWC provided Cult of Mac with a review unit for this article. See our reviews policy, and check out other in-depth reviews of Apple-related items.


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