MasterCAM blows absolutely every open-source solution out of the water. It isn't even a competition. In this case, it is actually cheaper to buy their really expensive and restrictive license, because in the end you save a near immeasurable amount of time in modeling, drafting, programming, and production. The fee CAD programs that can even support a postprocessing operation (becoming closer to a real CAM solution) are really bad at it and the toolpaths are far from ideal.