Probably not an issue for 99.99% of the population, but last time I checked, Untangle does not support IPv6 and has no plans on doing so. Also, Most of the interesting modules require a monthly subscription. I ran Untangle as a vm on an vsphere 5 hypervisor for a couple of years and it did the job ok. However, it is a cpu and memory hog which is surprising for being a firewall/security appliance. And probably the most annoying is the horrible user interface. They tried to make it look like a rack which is just silly. You'd be better off getting a Zyxell Zywall USG and mounting it in a real rack.