I painted my TF Spitfire entirely using my Testors Aztec airbrush. This is the only brush I've had, so I cannot give comparisons. The brush was about $100 us with 6 or so tips. I already had an air compressor which I picked up for another $100. I got a better regulator than what came with the compressor, and got a couple of disposable inline filters. I used exterior latex house paint for the major colors. I took color samples down to the paint shop and had a quart of each color mixed. It took a little trial and error to thin the paint to the right point, but once mixed, it went on quick and smooth in a couple of coats. The markings and weathering were done with Model Masters and Humbrol paints. The nomenclature was done with ink jet decals. Latex is not fuel proof, so after letting the latex thoroughly cure for about 2 weeks, I clear coated the plane with waterbased polyurethane. I used rattle can satin wb poly. Next time, I'll not use the rattle can but use my airbrush or hvlp gun as the rattle can leaves a bit of an orange peel texture. It's not real noticable unless pointed out, but I'm sure an airbrush or hvlp gun will give better results.
Here's a couple of shots before and after weathering.

Scott