I guess it depends upon how detailed the work you wish to do. My airbrush is a relatively inexpensive Master brand, actually two airbrushes and a compressor in the set. It does a wonderful job for tinting and highlighting cakes, but I've never been able to figure out how to do fine, detail work. It very well could be possible and I just have not yet learned to use it properly.
I've also heard good things about the Dinky Doodle brand, which is small enough to be easily portable.
For those purposes, I think most brands would work. My little cheapie would.
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