In terms of getting to an exact location, the most efficient is no vehicle, walking.

Cars are less efficient, followed by busses, then probably trains, then boats, then airplanes (unless you parachute).

Cars are the least efficient in terms of moving large numbers of people from places they can then walk from.

Weirdly enough because of the way mergerfs does writes across multiple drives, the main issue that FUSE filesystems face performance wise (namely writing a bunch of small files and their metadata) actually gets pretty well mitigated.

Who needs RAID when you have mergerfs

I’d say this seems useful mostly for pulling non nbz/torrent sources from readarr and lidarr services