I have 2 firewalls on my network ... an expensive Cisco Pix 515 and a not so expensive Phoenix Adaptive Firewall that resides on a Linux Box .... for me the Phoenix Firewall has made the difference , the Cisco one SuXXxxxx Big time .... a lot of the bad guys know all the funny glitches of the pix ... hasnt been the same thing with the Phoenix
My humble opinion anyways
FeLoNiA