In terms of performance, ADATA's SE800 Portable SSD is a solid offering because it supports the fast 10 Gbps USB 3.1 interface, which has now been renamed to USB 3.2 Gen 2. The SE800 achieves read speeds of over 700 MB/s, even at realistic queue depths. Technically, the drive can hit 1 GB/s to saturate the USB 3.2 interface, but that's with four or more parallel IO threads, which is somewhat misleading as such usage is completely out of scope for any external drive. Sequential write speeds are good, too, with over 500 MB/s. Both of these results make sure you'll be able to copy data on and off any SATA SSD at its maximum speed to keep transfer times as short as possible. We previously tested the Crucial X8, which is a little bit faster, but uses QLC flash (not TLC, like the ADATA SE800). When copying large amounts of data in one go (200 GB+), the Crucial X8 will exhaust its pseudo-SLC cache and thus end up writing at lower average speed than the ADATA SE800, which starts out lower, but stays fairly constant in write rates.

The backbone for this capability is the Innogrit Shasta IG5208 controller, which has some clever new tricks to optimize SLC/TLC write performance—reaching 510 MB/s on average with even tons of data written. One drawback of the IG5208 is that it does not support DRAM caching, which has a negative effect on random write IOPS. For a portable SSD that's a complete non-issue in my opinion, as you're not going to store any enterprise application's data on it directly while the application is running. Copying the data directory (a large database, for example) is no problem, though, as that utilizes sequential transfers only, which aren't affected by the lack of DRAM cache.

In terms of looks and physical design, the ADATA SE800 does great. With 7 cm, it is shorter than most external SSDs because ADATA designed their own PCB for the SE800. Other vendors design only an M.2 to USB adapter, plug one of their currently shipping M.2 2280 SSDs into it and wrap a case around that, which results in a length of 9 cm at minimum. ADATA did include a power and activity indicator, which is useful for when you want to be sure that activity has stopped and you can unplug the drive. Cables with USB-C and Type-A support are included, they are a little bit short, though. Most desktop computers have their 10 Gbps USB port(s) at the back, so a 25 cm cable means you'll be crawling under your desk several times. Thanks to an IP68 rating, the drive is protected against dust and water, which is a definite plus and ensures your data is safe on the go. It would have been nice to see some disk encryption, like on other portable SSDs, to protect your data in case you lose the drive. I'd also like to see bigger capacity options, building a 2 TB or 4 TB model should be easy for ADATA.

Priced at $175, the SE800 is fairly expensive. I'd say a more reasonable price point in line with competing offerings would be around $150. We previously reviewed the Crucial X8, which is one of the strongest alternatives because at $130 it is very affordable (due to its QLC flash), and it offers higher transfer rates. However, thanks to its great pseudo-SLC implementation, the ADATA SE800 will shine when you copy a lot of data onto it, delivering better average write speeds. Also, if you don't have an NVMe drive in your system you wouldn't be able to go beyond 500 MB/s write/read anyway.