I've test-run f2fs (https://en.wikipedia.org/wiki/F2FS) on several laptops and various devices booting from external USB/MMC devices in the past month. The subjective perception of the change in performance (from standard ext4) is evident. I was thinking very seriously about changing all my non-HDD-based devices to f2fs when I stumbled upon this:

https://www.usenix.org/system/files/atc19-jaffer.pdf

Basicaly, it says that f2f2s doesn't do as much checking for hardware errors as ext4 and tends to fail silently when there's a problem with the physical medium. This worries me and makes me want to stop using it - but the paper in question is more than a couple of years old and f2fs has continued to evolve, patches have been submitted to the Linux kernel and so on.

Anyone using f2fs care to share his/her experience with it?