ive been using kodi (xbmc was better moniker) since google killed sagetv. i recall attempting plex, but it seemed to lack some open/extensibility (its been awhile).
i have a side project i want to make as a modular plugin generating a cable layout with original air orders and networks/channels... kodi seems most optimal, but ill admit its been a long while since i looked at plex.
I know they could close up shop tomorrow, but the one-time-purchase of plexpass beats any sort of ongoing subscription. It does a great job of finding subtitles, it doesn't care how shit my file/folder structure is, and the client is user friendly for the rest of the house.
I prefer jellyfin, but I haven't taken the time to get my library in the right layout for jellyfin to display it right.
Have never needed it, almost all my media is just x264 so it's working on every potato around. Not the same answer for everyone obviously, but useless for me.