Your comments

I just found CintaNote, it's great, love the Simplenote sync.

Been a Simplenote user for some time now and have lots of notes already in Markdown.

The simple solution for me would be to use plain text in CintaNote, and have the sync respect the Simplenote Markdown flag...It seems when a note is edited in CintaNote, it resets the Simplenote Markdown flag to plaintext, so then I end up with unformatted text in both places.