I am now printing with my RF 640. On install we found a manufacturer error, where the head kept hitting the upper cover and would come to a stop. My installer had to add washers to the cover connect to bump it up, so the head could pass. We needed to do this on both ends. It calibrated properly, and so far is printing good. I am using Onyx, but notice that when I print a "non cut" file, and use versaworks instead of onyx, it Seems like the profiles print cleaner. Having a separate plotter vs. A print/cut seemed to be the most challenging issue, and I ended up with an onyx upgrade as the only solution that seemed to work with all machines.