4 hours ago, Keki1010 said:

Only a Sith deal in absolutes,

I will do what I must... ASK you something.  

Can you paint SFDP with a brush? Or is an air brush set ultimately the better option? 

Seconding what Dras said in my own way - and I'm also removing the medium as that doesn't really matter - what I'm about to say can be said for painting on canvas, or body art.

Airbrush is a tool, like any other. To go for a carpentry analogy: You can use a drill press, or you can use a plunge router. They can both get you mortises.

Even with my airbrush there are times I need to use a bristle brush, and likewise there are times when I used a bristle brush where an airbrush would've made life easier and possibly given me the same result for less effort.

I think it's a graduation thing. I do feel that there is a certain point in one's painting career where getting an airbrush will open up doors, but there are ways around not having one.