Over the years, I've had to buy quite a few external SSDs for myself and my friends – professionals in the video creation field. At first glance, all portable SSDs seem pretty much the same, but in reality, I've found that choosing one isn't as simple as just buying the fastest or cheapest one on the shelf.
The most important thing with portable SSDs isn't the theoretical maximum speed, but the sustained performance under real-world usage conditions. We often use external SSDs differently from internal SSDs. Of course, you can absolutely use a portable SSD for the same tasks as an internal drive. Personally, I still use an external SSD in my laptop to store my Steam game library, and it works fine. However, the performance certainly can't compare to an internal drive.
For most users, the question to ask is: how fast is the drive when you're continuously copying 100GB of data? If after just a few minutes the speed starts to drop due to overheating, the controller failing to keep up, or a lack of DRAM caching, then those impressive speed figures on the box are practically meaningless. The only way to know this is to read serious reviews, including extended tests of large file transfer speeds.
Beyond sustained performance, write endurance is an extremely important parameter for external SSDs, even more so than for system drives. This is because SSDs wear out primarily through the process of writing and deleting data, while external drives are frequently used to copy files, delete them, and then copy them again. SSDs are not suitable for long-term storage; if long-term backups are needed, external HDDs are still a better option. Therefore, instead of spending money on the highest speed, you should prioritize drives with good quality and a higher TBW (total write capacity) rating.
Security is also a factor that shouldn't be overlooked, especially with portable SSDs. I'm not too concerned about securing my game library, but portable SSDs are often used to carry sensitive data. If you travel frequently, or risk losing the drive or being checked at the airport, built-in hardware encryption is a big plus.
Drives like the Samsung T7 Touch offer 256-bit hardware encryption, eliminating concerns about operating system compatibility or performance degradation during decryption. Of course, you can still use BitLocker To Go or other software solutions, but hardware-based encryption allows for greater flexibility across multiple devices without complicated setup.
The physical durability of an SSD should also match how you use it. A compact SSD that fits in a MacBook's shockproof case doesn't necessarily need to be waterproof or drop-resistant. But an SSD used in a camera, or carried by someone working in the field, could easily get wet or dropped unexpectedly.
Personally, I really like using inexpensive adapter boxes to turn old internal SSDs into portable drives. This method is both economical and flexible, and you can even choose a shockproof case if needed without spending too much money. If your old NVMe SSD isn't heavily worn out, reusing it is very reasonable, because the bottleneck when using USB is usually around 1GB/s, even though newer ports may be faster. With external SATA SSDs, many drives can still approach the theoretical 600MB/s of this interface.
Another important point to note is that if you're using an NVMe adapter for an M.2 SSD, choose one with a heatsink. Even if the metal casing does some cooling, heatsinks are still essential to maintain stable performance and prevent the drive from failing due to overheating.
Finally, there are features I completely disregard, even considering them drawbacks when choosing a portable SSD. RGB lighting or flashy decorative details are just a waste of budget – that money should be invested in actual speed or durability. Similarly, overly elaborate designs or 'fashionable' looks aren't what I need in an SSD. For me, it needs to perform reliably and last a long time, not look like a stylish accessory.