do you apply any undercoat before you brush paint? A cheap automotive spray/aerosol primer works wonders.
Have to agree with Missy here, once you go down the route of an airbrush, you won't want to come back. Admittedly it is a big outlay, compressor, airbrush, thinners, time spent cleaning up etc, etc. Fortunately for me, I've been using a mates for the past 5-6 years, we used to have annual spray days. Now that we live 1600km away, it’s not really doable. Last year Mrs Noswal bought me a compressor and accessory pack for my birthday. Now, not only can I paint when I want too, but I inflate tyres, blow-up toddlers pools (what used to take 45 min of hand-pumping is now 5min), and other husband like jobs requiring high pressure air! I know air-brushes are expensive, but try eBay, I got a cheap one, for starters, from Hong Kong, for only $2 plus $10 postage. What made it even better was that it was listed under the finger-nail art section. The same air-brush in the modelling section was $35! All you need to do is practise.