Ran close to 500 45-255rf through the oven this afternoon in a steady rain, all it's done for the last 3 days. I used a grey color that Randy Rat sold on the other site a few years ago. Not sure what it is, but it goes on pretty good, fairly thick. I ran a test batch just to see if it would work in the rain, humidity was high enough that the floor of the shop was wet. Test batch looked good, so I went ahead and got a decent supply set aside. That and a gloss black that I got from pbtp are the only ones I've tried. Having a hard time getting myself to order the brighter colors, but as Ian said, the yellow green and medium blues seem to be about foolproof. Need to order some clear one of these days.