Things have been going well for me, using docker-mailserver.

I followed the setup guide, did everything in the DKIM, DMARC and SPF documentation page. The initial setup required more involvement from me than your standard docker-compose self-hosting deployment, but I got no issues at all (for now, fingers crossed) after the initial setup : I never missed any inbound e-mails, and my outbound e-mails have not been rejected by any spam filter yet.

However, I agree with everyone else that you should not self-host an important contact address without proper redundancy/recovery mechanism in case anything goes wrong.

You should also understand that self-hosting an email address means you should never let your domain expire to prevent someone from receiving emails sent to you by registering your expired domain. This means you should probably not use a self-hosted e-mail to register any account on services that may outlive your self-hosted setup because e-mail is frequently used to send password reset links.