you can still try V2.0 but as we all are stating 2.0 isn't ready for true production environments BUT its can be used but we STRONGLY suggest using 1.2.x, if your ok with taking it into a production environment and testing it and are willing to accept that there may be bugs and potential down time and want to use 2.0 we won't stp you, we just are trying to let you know if you do use 2.0 in a production environment just be ready for things to break and down time to happen with it.
now if your looking for an actual firewall appliance perhaps something called endian may fit your needs, but again thats the same basic situation, if you are using a custom machine you run the risk of incompatibilities being there…and the actual appliance will run you from about $150+ depending on what you need...if you need other options there might be other linux based firewalls out there you might be able to try.