My wife gave me some old make up brush's and I found a couple sets of them on clearance at the Pharmacy. And I use the cheap plastic ones from Wally World too.
I use cheap cheap brushes. Has more to do with how much powder is on the brush, hard you tap, and how far away you are from what you want to paint. I actually recently added a new thicker brush to my other favorite for when i want to lay down more powder per tap. Just takes playing around with it.