There are two downloaders I use:

4K Video Downloader - Adware or $15. This is my primary. You can choose which resolution to download (or even just audio). It does one download request so you often get to complete a download even if the vod is replaced mid-download (e.g. with a DMCA muted version). But other times the replacement vod confuses 4kVD and it keeps restarting the download indefinitely so you have to keep watch so it doesn't suck up all your bandwidth. The app is regularly updated as video sites change their pages (it's basically scraping the target page looking for download links) though sometimes it can take a week or two before an update is pushed out.

ViDL for Mac - free. This packages some open source tools and adds a simple UI. It downloads the best quality version it finds. It uses multiple threads so if the vod is replaced mid-download you end up with a corrupted file. One key feature is it supports login pages. Some Twitch channels only subscribers can view vods. ViDL can show the login page and you login as if on a web browser then ViDL has a one-month token it reuses.

So for vods I really want:

1. Wait for stream to finish
2. A few minutes after end use 4K Video Downloader to get vod (or ViDL for sub-only vods.
3. If 4K Video Downloader fails, cancel and try one more time.
4. If 4k Video Downloader still fails use ViDL.

Rarely a streamer deletes a vod right after stream ends. If you're afraid of that use 4K Video Downloader to start the download before stream ends. You won't get the whole stream but download should leave you with a viewable file.

I've also used JDownloader 2 which is open source but too many options. It seems to be like ViDL with more controls.