I've been trying to get on ripping my dvd library, but some of this stuff flies over my head:

Can you give me a gist on what a "remux" is & why you prefer it over encoding it? From the context it seems like it's similar to lossless vs lossy codecs for audio?

Happy to add remux support! I'll get it on my backlog. Probably should have some kind of configurable output profile rather than just HEVC or remux

Sure, but that takes a lot of time and effort when you have a complicated stack, so it's nice to be able to handle it in two clicks instead of setting up an entire encode queue while cross referencing all my metadata so I get episodes mapped right. Often a series session will take me upward of 30 minutes to set up an encode queue manually. With Discarr, it takes me 30 seconds

Edit: this came out of many attempts to create a single script that could post-process torrents, unpacking archives or converting disk images dynamically. The trouble is that dvd formatting for series follows no standards whatsoever, and really requires a human to map the titles. Discarr automates everything except that, and surfaces the title and episode queues side-by-side to allow quick identification and assignment

Sonarr/Radarr occasionally grab disk rips as they're the only format available for certain titles, but they can't be directly imported without conversion. This fills that gap cleanly.

I've never used this software, so just guessing here, but if radar/sonarr are not aware of the mkv file they will attempt to find the media which would result in duplicate files