One thing to say to this.. I work at a company and have personally setup quite a few mail servers for mass email sending and warming up IPs.. not fun.. (these

One thing to say to this.. I work at a company and have personally setup quite a few mail servers for mass email sending and warming up IPs.. not fun.. (these are all legitimate interest emails) I was in a meeting with a couple of people from the team and a QA engineer mentioned that everytime he's done with an email in gmail, he spams it off... _wut_.. Whilst yes, we have been blacklisted a handful of times and, based on spam reports (feedback loops), people do mark emails as spam for completely nonsensical reasons... e.g. users signing up, (getting and using the activation email), using the service and then spamming the activation email. Edit: I definitely think there's a bell curve for sending your own emails: * If you have a very small platform (at least in my experience), reputation doesn't mean that much, emails are generally accepted by providers (assuming IPs that you used haven't been previously used for spammy activity), so self-hosting might make some sense (though a third-party probably wouldn't be too expensive if you did want to). * If you start sending 100s-1000s of emails/day, I guess some third party solution would make sense, since running dedicated IPs/domains and servers just for sending emails might not be beneficial. * As you go to sending 100K+ emails a day, personally, I think setting up servers starts making more sense