Double VS. Single ( Just My Opinion )
Opinions are like axxholes ( Everyone Has one ) with this said here's mine.... ( opinion that is )
Obviously Single action is easier to master for a beginner than the double action. A single action has a whel at the top to adjust the air pressure and needle tips to change the paint. Les air - less paint. The single action is easy to master and is used by allot of artists for latex paints. due to the external mix. The dual action requires more control since the trigger is adjusted 4 ways.
I myself own 4 Paasche brushes and one Badger 3 siingle action and 2 double action brushes. I am partial to the H single actions for simplicity. I use these for the average job. I use the dual action for more detail less grainy jobs.
I also have Carpal Tunnel and Athoritis so my airbrushing days are coming to a close so the H single action allows me to airbrush more comfortably. What's hard about the double action is that you have to push down and then pull back. ( take yer pointer finger of yer dominate hand and act as if you are holding a pencil pushind down on a button with yer pointer.... now pull back with yer finger. Now remember if you move a little you just made a mess of your work ....LMFAO.... its a pain in the ass. BUT MASTER THIS AND YOU'LL HAVE BEAUTIFUL WORK!
Its just my opinion ( get both ) try them out they both have different uses... But I think you will be very happy with a Paasche H
( Good Luck )