Most model boat hulls are way too big for an airbrush and in fact, even a spotting gun on a decent compressor can take a while with it's small spray pattern, but a rattler can ain't gonna last long on say a 30" hull. I'd say brush paint with a decent enamel, like HMG.
I have always used rattle cans from Halfords and or The Range. Beware of mixing different types of paints i.e. cellulose, acrylic and enamel. I have had a disaster with mixing paints that took weeks to strip the hull back to sort out.