Alan,
Give the Vectric demos a try if you haven't already. I don't know how many times I carved the "puppies in a basket" demo under PhotoVcarve but it was quite a few while I was tuning the parameters (steps per inch, acceleration, velocity, etc.) in EMC2. I just use the G Code (inch).tap or G-Code Arcs (inch).tap postprocessors. So far I use my Windows PC for CAD/CAM, copy the gcode to a usb flash drive, load it onto my Linux EMC2 PC in the garage, and run it. It's definitely nice to have a dedicated machine controller.
Justin