Portable SSDs can offer amazing speed for content creation applications like transferring photo libraries or editing 4K video, but many suffer from a slowdown after prolonged use when their faster cache is depleted or the drive heats up too much. ProGrade has announced a new line of portable SSDs designed to address both of these issues: the PG10 Pro SSD.
Just like how good quality memory cards advertise burst and sustained write speeds, the PG10 offers similarly descriptive ratings. ProGrade specifies read and write speeds of up to 2,500 MB/s, with sustained write speeds of 1,500 MB/s for the 2 TB model and 2,000 MB/s for the 4 and 8 TB capacities. To enable these speeds, the drive features the blazing-fast USB 4.0 interface, which is also compatible with Thunderbolt 4 and 3, as well as USB 3.2 and 3.1 Type-C ports (although the slower USB 3.x implementations will prevent this drive from reaching those max speeds).
While these are solid specs for a USB 4.0 external SSD, the sustained speed aspect is what's really important. On some SSDs, the drive is designed to write to DRAM or a buffer of faster NAND memory first, then fall back to slower NAND if the write operation continues. In most consumer applications, this isn't noticeable, as you get the fast write for 5, 10, or more GB, and the operation concludes with the drive "flushing" that cache in the background. In other applications, like writing heavy 4K footage for a half hour, however, that initial cache is depleted, and write speeds fall sharply. While ProGrade hasn't provided additional details in the launch announcement about how they are handling this, they did show testing of the drive maintaining a 1.8 GB/s transfer rate even after writing to the drive for 46 minutes, drastically outperforming what they characterized as a "competitor SSD," which dropped after just 10 minutes.
The design is standard professional external SSD looks, although ProGrade has included some nice quality-of-life features with the drive: a power-sensing circuit and LED to inform users if the host device isn't providing the requisite 15 W, a magnetic base for drive stacking or workspace mounting via the included adhesive metal plate, and a hard-shell carrying case.
While I haven't been able to test the drive yet, I've worked with previous ProGrade products and found them to deliver on all the claims. These drives are really intended for power-users who are going to transfer hundreds of gigabytes or even terabytes of footage or files at a time, which is where you'll really notice the sustained write performance difference.