I switched to Migadu yesterday after seeing some positive reviews here, and I’ve no complaints so far.

+1 Been with Migadu since 2017 with no complaints. Lost some mails on an account due to a migration of sorts on their end though that was eventually restored after a ticket.

Michael and his crew are fantastic in progressively introducing new features that you may never find elsewhere (https://www.migadu.com/guides/index.html#features).

Your end users may hate the sparse webmail features though that's nothing that Thunderbird or Outlook may not resolve. HTH!

Fastmail is not a good replacement for family needs because it’s quite expensive at one mailbox per person. Those who need multiple mailboxes should look at other options.

Or ProtonMail, which is outside of the Five Eyes!

If you're doing anything substantiative enough to warrant investigation by a big government, that won't help much https://www.bbc.com/news/technology-58476983

What are they supposed to do when their own government has a warrant? Ignore it and let the government shut down the whole site? This way they followed it without breaking anyones encryption, no back door, … this is a positive aspect in my view.