I started out with a $20 cheapy airbrush, which did ok.
Purchased my first real airbrush, an Aztek 4709, and much to the shock of a few people I liked it alot.
Managed some really decent kits with that one.
Purchased an Omni 4000, and was very happy for a couple of years, but needed more.
My latest purchase was an Iwata HP-BS with Preset Handle, and I have to say that it is the best feeling airbrush to date.
It really does the things I need and ALOT more, worth every cent IMHO.
The Omni will still get alot of use, really is a great brush for the price, but the Iwata is now more choice for detail work, like squiggle camo and mottling in 1/72 and 1/48.