It is a) very old, b) no longer actively being developed.
So it wouldn't be keeping pace with exploits (leaks) to by-pass the firewall, so my answer would be a) no I haven't tried it and b) not I wouldn't try it.
In its day it was a very good and highly configurable firewall, but even then it had vulnerabilities with the localhost loopback, e.g. it only challenged the localhost proxy parent and not anything else that happened to use the proxy.