Researching OpenSolaris 2010, a free System V UNIX, I come across a website that explains that in order to compete against Red Hat Linux in Government security requirements, they had to make the price point equal Red Hat's with only the customer service charges. So Red Hat was the first and one of three Linuxs to get EAL4 Augmented with ALC_FLR.3 including RedHat Linux, Oracle Linux, Suse Linux which is why the US Government is the largest buyer of Red Hat Linux. It only took OpenSolaris a year to be created after Red Hat accomplished this. The question is which one would you pick if customer service and patches were comparable with the latest Red Hat Enterprise Desktop? OpenSolaris has ZFS. I'm using OpenSuse BTW! Northrop Grumman likes Suse Linux too.