You've seen a comparison between OneCNCXR compared to OneCNC2003. OneCNC2003 had the "nuts and bolts" of the basic system, so to speak. But XR has really gone wild on ease of use, and is very far advanced over the 2003 series in this regard. Although OneCNC2003 did "save my bacon" back when I started using it, I never felt that fluency in using it that I experienced in XP, now grown to XR. Its a great feeling to know that you can easily tackle any 3 axis job that comes along, which I suppose represents the vast majority of all milling work.