DTP or external Markdown editor?

I am using the integrated MD editor of DTP. I try to use additional apps only if they offer a relevant benefit. Are you using external MD editors?

1. If yes, which editor do you use?
2. which benefit do you see over DTP’s editor, which is already quite good!
3. do you open DTP MD files in the external app by clicking on the icon in the menu bar or do you open them with a shortcut? if yes, how?

Thanks a lot for sharing your experience