Preferred Email Server Package?

[JordanN]

I need to setup a mail server, and it will be my first one. We have a few users, and several domains. Usually, the other domains are simple redirects.

If I have to leave for some reason, I need to know that the next administrator will have some hope of resuming where I left off, without having to redo everything.

How does QMail compare to Postfix and Sendmail in the areas of:

• Ease of Setup (Do I have to write lots of code to just make it work?)
• Ease of Maintenance (Adding users, moving users, adding aliases, adding domains...)
• Security (Does it have lots and lots of vulnerabilities, does it interface nicely with SpamAssassin?)
• Neat Features (Web management interface, user features)

Thanks!