Spike if you are using an
airbrush your best paint is the Vallejo Model Air which is specifically produced for airbrushes. Vallejo Model is best left for hand brushing although it will
airbrush with a large amount of thinning plus with a .4 or .35 needle nozzle.
Vallejo recently brought out their Flow Improver which has made a heck of an improvement. Use this and you will reduce the blockages to a very minimum. I rarely get a blockage.
Also it is a great thinner I have used it 50% Flow Improver to 50% paint to produce my own washes. Works perfectly through a nozzle needle combination of .2.
For me I would rather thin to 15% to 20% and apply two coats rather than one thick. You will be able to apply the second coat, depending on conditions, after an hour or so.
Stewart