Hello,
I use JPS paints frequently. They spray very well through my Anthem 155 airbrush. I thin them roughly 30%with isopropyl alcohol. I have also thinned them with distilled water, which seems to work just fine. The paints cover and set well. I always prime my models with an enamel primer so I cannot say how well the paints "grip" an unprimed surface, although I have never seen anyone complain. The RLM colors look accurate to me and match the paint chips found in the "Luftwaffe Camouflage and Markings 1933-1945" volumes very closely. They take both future and a variety of matt finish