RE: Spray technique?
John, at this point I'm in the final stages of finished a 1/6 scale Sopwith Snipe. All that remains in terms of finish is some weathering and clear coating. I've used Nelson's paints for the PC10, roundel colors, and markings and model acrylics for the grey turtledeck and metal panels.
The Nelson's paints produce a very authentic and fuel proof finish once you figure out how to use them. It's possibly the best finish I've ever had on a model. It looks very much like an authentic dope finish -- and it's water-based, which is a huge convenience. Up to this point everything's been hand-painted. The basic color was put on with dense foam brushes. The roundels and rudder numbers are essentially "freehand." This was actually much easier that I had imagined once I learned (from people here on the Scale forum) the appropriate techniques. The bars and large E's were masked and then hand-painted.
I sprayed acrylic on the metal panels and I would have liked to be able to spray on a clearcoat -- then do a bit of weathering and then spray on a second clear coat. But I haven't been able to get a good result yet with spraying either the PU or Nelson's Clear.