Tried Agenda as a sort of Drafts for the Mac that syncs to iOS. I found one, small fatal flaw: Paragraphs do not have blank lines between them, making it impossible for me to compose on Agenda and cut-and-paste to plain text.
I mentioned this on the support forums and the developers said they have no intention of changing how that works because the applications that put blank lines in between paragraphs are doing it wrong. They suggested pasting to multimarkdown as a workaround.
This sounded like a hack to me and so I abandoned Agenda.
And now I’m using the DevonThink note taker as my Drafts for Mac.