[dqv]

Not the person you’re replying to, but

I’ve been running MIAB (mailinabox) for business and personal since 2016. I haven’t seen any major issues with deliverability but YMMV. You have to register with all the feedback loops. Once you do, you get feedback when something you send gets marked as spam. Spam on MIAB is handled with postgrey and with spamassasin. It’s pretty good, although I’ve had recent issues with spam coming from gmail and hotmail. I’ve also customized some of the config to bounce Microsoft Sharepoint and Google Docs since neither companies control spam coming from their networks.