I have mentioned this stuff before, and yes, it rocks! I airbrush it mixed 50/50 with distilled water at about 11 psi through a Badger 155 anthem (siphon feed). It dries dead flat, clear, and cleans up easily with Windex.
One word of caution, stir like crazy before airbrushing, if it settles, the matte medium is on the bottom of the bottle, and while it still sprays nicely, you get a lovely satin effect.
I have not tried adding it to paint (or vice versa) as I prefer my sprays in stages, and can't imagine why I would need to apply paint and varnish in one coat. I haven't tried the gloss version yet, future has always worked well enough for me, but I may give it a shot one of these days.
Chris
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