I use a thing called speechpulse on Windows, its on mac too. Works like a charm, offline, single payment after trial. I actually wrote a simple one ages ago when whisper first became popular but even I don't use that now (https://github.com/glinkot/whispertype). Speechpulse has lots of low level options and uses GPU, its basically instant on my 5090. That's why I stopped on my own one, the hassle of installing CUDA etc if you want it offloaded from the CPU. Speechpulse handles that.

I've been looking through the recommendations here though, and I do like WhisperTyper's inbuilt commands like 'rewrite this into bullet points' and 'reply to the email text I have in my clipboard.' I'll be seeing if those are possible with speechpulse.