First up I use a Badger 155.
My favorite quote on airbrushes is from NIB,"It will shoot pebbles"
You have to have a steady hand and very fine touch control ( something I learned early with girls and now have been able to apply to airbrushing) Being ham handed (George

) will not serve you well with an airbrush.
I use Createx paints, thinned and un-thinned, Daler & Rowney Pearlescent inks, which some say are not for airbrushes but I have never had a problem with them both spraying or cleaning. I have also used Testor Oils and Luminaire pigments as well with no problems.
I have an old beat up compressor that sounds like a Model T but works fine and have not yet had the need for a water seperator, I have one but never installed it. The compressor has a built in pressure regulator which helps when doing fine or production painting.
I am looking for something which will give me more detail as I like to free hand effects like vermiculations and such.
I have serious trouble though scale painting with the 155 and that's a main reason why I would like a strictly detail oriented brush.