Anti-Spam Router -- opinions?

["Andy Johnson" <andyjohnson () ij net>]

Has anyone had any experience with this device? Turntide.com. Looks like a
traffic-shaping device designed specifically for cutting down spammers
throughput to your inbound SMTP servers. My main concern is, how does it
make the distinction between legitimate mass-mailings (e.g.: mailing lists
such as this one), and spam? Interesting approach to killing spam though I
must say.

-Andy