If you look at real life performance benchmarks of flash drives, differences in most scenarios are so small, it is unlikely anyone could tell the difference in blind test, but good ones are still much better in certain scenarios like when writing huge files and especially when writing huge files on a (nearly) full drive.
Important things to know and look for are:
- Write endurance is affected mostly by two factors, what memory cell technique is used and how large the drive is. If drive is double the size, write endurance is twice as good too. While other memory cell technologies exist, the most common are TLC and QLC. TLC drives almost always have "enough" write endurance for typical home/office/gaming use, but if you but a QLC drive, make sure it has enough capasity as you can actually wear down a small one in a couple of years. I would not buy a QLC drive smaller than 1 Tb at least if you plan on using it as a system drive and even then... Rather use it as a storage drive or get a 2Tb one. TLC is a better option as system drive. SLC would be great, but not economically feasible for most.
- Make sure it has DRAM cache. Cheapest models don't and that is a very bad thing.
- TRIM support... very common, but don't buy one that does not have it.
- Do not fill up your drive. When considering how much storage space you need, always take in to account, that if you fill your drive, it can drastically slow down, it's endurance suffers and so on.
- Sequential read/write performance doesn't matter much in real life use. That is why you really need to check benchmarks before buying anything.
So which drives are fast:
(1) Intel Optane **(to my knowledge, they don't make them anymore)
1) Samsung 990 Pro (likely - haven't seen bencharks yet, likely not available yet)
2) Seagate Firecuda 530
3) Kingston KC3000
4) Western Digital Black 850
