Problem is not the actual spraying of the coating, but the clean up afterwards when you going to use Epoxy thinner or acetone to clean the air brush up in the end.

If you want to use a cheap HF air brush, then hit up a plumbing supply store (bell plumbing supply will have them) to pick up the needed O rings (about a dime each since they are so tiny) that you are going to burn up each time you go to clean the gun.  As for the plastic bottle that comes on it, you can swap that out with a tester paint bottle instead.

My craptasitic HF airbrush for down and dirty  quick  light work.



Now on the other hand, if you want a hell of a lot better air brush, then I also have a Iwata Eclipse HP-BCS with glass bottles that the internal seal and bearing on it have been replaced with teflon parts to make is solvent proof as well.  When you go to order a air brush, make sure it has the teflon Upgrade done to the air brush, has glass bottles,  and even have them send you an extra upgrade parts seal kit  as well.  Hence did not get it clean up, need to soak the seal parts in acetone to get the last of the crap off them, and don't feel like waiting for the parts soak clean before you can use the air brush instead.  The upgrade kits are only around $20 for all the parts.
Note, you can get Badger air brush that have been Teflon seal and bearing upgraded to make them solvent proof as well.

As for the reason for my HF and the Iwata Eclipse, it a needle vavle system that allow for quick clearing of the nozzle if you start to get a clog in the gun.  Hence you pull back of the trigger button to pull the needle back out of the nozzle to run it wide open, and most of the time will clean the clog quickly.  Worse comes to worse, drop the coating bottle out, install a bottle of pure solvent into the gun, pull back on the button again with it depressed to spray to a paper towel, and it will clear the gun of the worst of clogs.

As for why I use a air brush, isntead of a HVLP gun, I can get different finishes from the same coating isntead.
Hence from flat black Duracoat (prolane T), I can get a finish that will mirror parkerizing in texture, to a finish that will mirror  high polished bluing isntead.