I use several different airbrushes, most are double action for a variety of different needs. But my most frequently used is the old steady Freddy Badger 200, both the basic version and the gravity feed 200G. For solid colors and primer coats it's unbeatable, simple and reliable, easy to clean, tough as a hammer.
I have Badger, Iwata, Paasche and Binks in the inventory, after many decades of airbrush use I'm strictly in the Badger camp. Reasons follow.
)1 Very robust materials and build quality, they are just plain durable to an extreme.
)2 If needed, replacement parts are very low in cost in comparison.
)3 Low acquisition cost, especially when you take the time to watch for sales at the authorized dealers, like Chicago Airbrush and TCP Global.
)4 If service is ever needed, Badger factory is fast, inexpensive and friendly.
)5 My Badger's spray at least the same quality of finish as any of my others, often better.
I have no affiliation with Badger, just a very satisfied customer and I enthusiastically recommend them to others.
Patrick