I have been using it for my personal domain for a long time now and my employer for a slightly shorter time, and it works pretty well. The spam filtering is pretty good, but I have had a number of false positives, so I do need to check the spam folder regularly. Some false positives were very annoying - for example mail from a GMail user from the same domain who had sent it through the authenticated SMTP connection.



I know for certain that it works using a +, I haven't heard of a way to get it working with a dash.



It has Groups which should do what you want, but I haven't used it much.

Gareth