What I like the most about SpamTitan is the fact it is an appliance that can run as a Virtual Machine. It highly simplifies the implementation of the product in any environment or architecture. With SpamTitan it is easy to manage any internet domain and all the rules to them related.
I'm very satisfied with SpamTitan. We manage several installations on both single mail server and multi mail server configuration. SpamTitan is very easy to setup and maintain which makes it a perfect software for production environments.