I also used whisper.cpp to transcribe all my hoarded podcast episodes. Took days of my poor old CPU working at 100% on all cores (and then a few shorter runs to transcribe new episodes I have downloaded since). Worked as good as I could possibly hope. Of course it gets the spelling of names wrong, but I don't expect anything (or anyone) to do much better. It is great to be able to run ripgrep to find old episodes on some topic and sometimes now I read an episode instead of listen, or listen to it with mpv with subtitles.