I’ve just recently started using tdarr to convert all of my media to x265on 14/02 and so far I’ve saved 4.02 TB of what was 28.12TB media collection. (The number isn’t a true reflection though because new episodes and shows have been added to that library since I started)
I’m letting tdarr manage the conversion process and once up and running meant that my NAS, desktop, my NUC and a mini pc are all plodding through and converting when I’m not using them for other things.
If you are worried about the disk space being taken and have some CPU time you can devote to the conversion process then I’d suggest it’s worth looking into tdarr.