Since we're all posting about our favourite email provider, Purelymail has been one of my best discoveries of the last year or so. Ten dollars a year (though it's expected that price will go up) for as many mailboxes as you like. There's a webmail too in case you don't want your own IMAP client. I migrated every email I had (except an unmigrateable @gmail.com) to Purelymail over Christmas and I couldn't be happier.
I migrated to Purelymail around the same time! It's working great for me. Unlimited domains, unlimited users, easy to setup. I'm slowly moving all my accounts over to my own domain.
Purelymail is really good. I've been using it for over 4 years now and haven't had any issues around deliverability or availability. It might not be fancy but it has almost any feature you'd want.
I also love Purelymail. I love the fact that it's so cheap, but that also scares me, because I know it can't last forever.
I've had purelymail for several years. I've only had to contact support once. They responded within an hour and fixed the problem as well.
I've helped nontechnical people move to purelymail as well, they all love it.