I have used the Trak (prototrak) cnc's at one of my former jobs and I loved it! You are right about the g-codes. They are there, just not visable in the program they use to write your program part. They will save and eccept g-codes though. When you need short run or one piece it was great. At my last job I could not get then past the cnc machining center vs. manual machines. I think that both the prototrak or Centroid are great "go betweens" for a productive shop. I have not run a Centroid machine myself, but have seen the demo at a local tool show. Another thing about the Trak system- They use a encoder feedback off a metal wheel that "rubs" on the machine itself. They HAVE to be free of coolent, but otherwise worked well. Centroid uses glass scales. Hope this helps... Rick |