And none of them 3rd party audited which is understandable given the fact that a security audit is ~$15-20k, but still it's important. 

Most (if not all) devs are not qualified to audit their own creations.

I support developers developing, but I wouldn't trust my privacy when it matters with the Nostr chat apps, including Amethyst DMs which is markedly better due to NIP-17.

For now, I'll stick to Signal for privacy-respecting normie convos, and my properly configured SimpleX and Session apps when privacy is imperative.