your better off drinking the paint and spitting it on the model. I ruined several good models with this piece of trash. Even if you hook it up to a compressor, the air pressure is not consistent, the hose gets clogged very easily, and the pre-mixing instructions on the bottle basically tell you to waste an entire pot of paint for one dose.
Stay away, stay far away.
Additionally, I tried to bust into the air brushing scene a year ago, and I would like to give you a few words of advice that I could have used to save me a lot of headaches.
1. Find a mentor. The money you will invest into air brushing can exceed 7 to 8 hundred dollars in a hurry. Don't go by what the douche at the store says, or some internet forum

. Find someone locally that can take you under their wing and teach you, using some of their hardware. There may be classes in your area. Don't limit your search to just gaming hobbies either. Air brushing is very popular in other venues such as vehicles and wall art.
2. don't buy a cheap air brush. $100.00 minimum. Some would recommend much more. I wasted alot of money trying to buy cheap air brushes. I think that pasche has a $100.00 starter kit that is siphon fed. (paint is on the bottom). There will be air brush snobs out there that tell you to spend 300 dollars on a gravity fed dual action air brush, but you will most likely tear up your first air brush. Guess it depends on your disposable income.
3. Patience. You will probably have to dissasemble and completely clean out your air brush 50 to 60 times before you discover the right mixture of paint thinness. Everyone will tell you "the consistency of skim milk". that is really not much help if you don't know what you are doing.
My recommendation is this. Don't mix the paint in the airbrush. Find a cheap test color you are going to experiment with. My recommendation is yellow, because its hard to cover with, and is easier to see your mistakes. Mix several small vials of it with precise measurements. 60/40, 50/50, 40/60, and so on. Find the one that works for you and the paint you will be using. If its too thick, it will clog really soon. If its too thin, it will sputter and run. Paint it on foam board. both on black, white, and grey colored foam board. This allows you see how the paint behaves on different colors.
That's all the advice I can give you because I am still learning myself.
Just for god's sake, don't give
GW any more money for that stupid gun.
Rant over