I’m not sure how many times we are going to have to have this conversation before majority of people get the point. Using older firewall versions is not safe. No matter the brand name of software. Security software companies update these products for more than just marketing purposes. Many updates are done to resolve known security issues or usability problems. Yes many times new features are released with newer builds. However when looking at product history many times you will find that security updates have been done as well.