Sun Ultra 5 as a firewall?

[Joe S]

Is anyone on the list running an Ultra 5 as firewall? I would like to 
move my firewall from an overpowered P4-3GHz box to a Sun Ultra 5 360MHz.

My main concern is wondering if the Ultra 5 is slow enough to become a 
bottleneck from one interface to another interface. However, I know some 
of you run Soekris boxen and 486's for firewalls, so I may be just fine.

Any thoughts?