Alternatives to Postini?

We’ve been using Postini (spam filtering service) for some time now. It is effective, but learning and managing Postini is one big headache.

I’m looking for some strong contenders (alternatives) to Postini for consideration. Any suggestions?

Thank you,

We recently went through this chore.

The only real viable alternative we found was Microsoft Exchange Servers… but that’s kind of an all-or-nothing deal. We ultimately went with Postini.