Firewall decision

I am currently looking at either a PIX or a Cybergurad firewall installation to protect my private network & DMZ> We have approx. 100 hosts, an internal Mail Server, 2 internal Web Servers & a VPN & some fairly complex security req’s.. PIX is definitely the more cost-effective solution, but Cyberguard boasts superior technology & protection. any opinion on this? Has anyone installed the PIX firewall in an environment similiar to this? How is it working?

Thanks.

DB