Clearly, the CNC model is a backward step for 3D printing. Obviously though, there is a market in CNC users who want off the shelf 3D printing without leaving their comfort zone. The CNC arena is about big, expensive and tried and trusted technology (read : "old"). If you have space for a CNC rig, you have space for an obsolete PC with a parallel port, and a large controller box. If you have spenby bobc - Mach3