
SanDisk Extreme PRO 4TB USB-C
Score: 85/100
OWC Envoy Ultra 8TB
Score: 87/100Rankings

The OWC 8TB Envoy Ultra is a bus-powered Thunderbolt 5 enclosure delivering over 6000 MB/s speeds in an IP67-rated aluminum chassis. Its ultra-high performance comes at a premium price and may not reach full speeds on older Thunderbolt 3 hosts. It is best suited for professional creators requiring massive, ultra-fast portable storage.

The SanDisk Extreme PRO Portable SSD 4TB delivers Thunderbolt-class performance with up to 3800 MB/s read and 3700 MB/s write speeds in a rugged, IP65-rated chassis. Its peak speeds are only reachable on USB4 or Thunderbolt 4 hosts, and it lacks built-in hardware encryption. Ideal for creators needing ultra-fast portable storage.
| Attribute | ![]() | ![]() |
|---|---|---|
4 GB | 8,000 GBbest | |
3,800 MB/s | 6,000 MB/sbest | |
3,700 MB/sbest | — | |
| ↓ lower better | 172 gbest | 326.6 g |
5 yearsbest | 5 yearsbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Connectivity(1) | ||
Interface | USB4 Gen 3x2 | Thunderbolt 5 |
Build & Design(2) | ||
Weight (g) | 172 g | 326.6 g |
Enclosure Material | silicone shell, aluminum chassis | Aluminum |
Storage(1) | ||
Capacity (GB) | 4 GB | 8000 GB |
Performance(1) | ||
Sequential Read Speed (MB/s) | 3800 MB/s | 6000 MB/s |
Features(1) | ||
IP Rating | IP65 | IP67 |

Products in the top-left offer the best value (high score, low price).

Professional reviewers commend the Extreme PRO USB4 SSD for its Thunderbolt-class speeds, rugged construction, and real-world bandwidth that validates the advertised numbers. However, they caution that the full performance envelope is only reachable on USB4 or Thunderbolt 4 hosts, and that 4K random write performance has slipped compared to earlier USB 3.2 models, with endurance data still missing.
Everyday users largely echo the reviewers' praise for blazing transfer rates and the drive's durability, especially for on-the-go creators. The most common complaints revolve around slower speeds on legacy ports and the absence of clear endurance specifications, though no widespread reliability issues have been reported.



Professional reviewers praise the Envoy Ultra as a groundbreaking portable SSD, calling it insanely fast and the largest in its class. They highlight its bus-powered 6000 MB/s performance, IP67 ruggedness, silent fanless design, and integrated cable as key advantages for creative workflows, noting it enables previously impractical high-bandwidth tasks on Thunderbolt 5 systems.
No direct consumer reviews or ratings are available yet, as the product was only recently announced, so everyday user sentiment is not documented.