I recently was looking for the best USB Thumbdrive sold today and after much research ended up buying the
1TB T31 from SK Hynix, who make extremely fast and low power SSD replacements for older Macs like the 2015 15" MacBook Pro. This is the
best review out there on the T31. I opted for the T31 rather than the fabulous looking X31 only because I already own a
2TB SanDisk Portable Extreme SSD (which, like the SK Hynix, is also USB), and I find that I yank out the cable by accident because the SSD dangles down under my MBP in bed and I forget and it gets yanked. With a USB stick firing out the side, it looks precarious, especially with a USBA-to-C adapter, but I've never smacked a USB stick against anything before, which is why I went with the T31 in the first place. Here's
another review of both models.
Sadly, the SK Hynix drives only go up to 1TB in size, by since my own objective was a fast "Thumbdrive" I didn't mind that upper limit. The SanDisk goes up to 4TB, but some people have
reported data loss issues with them over the past year. I've never had data loss with my SanDisk, but mine is an older model (and slower) than the one I linked for you and is no longer sold.