In principle, it's a pretty good "all-in-one" server, and I even wanted to switch to them until I checked the documentation and saw that the Community version doesn't filter From with valid authentication. This means that anyone who is properly authorized can send an email from any address on the server out of the box. In short, if I understood the documentation correctly, it's a decent option for hosting your own mailbox, but for even small-scale mass use, postfix + dovecot still wins.