For my Gas Check designed boolits I still use checks but I don't coate the shanks. I ESPC using a tray with fender washers and non-stick aluminum foil. Works like a dream and doesn't allow the rifle boolits to fall over. I make my own checks from aluminum flashing using dies from PatMarlins. Only recently have I been annealing the aluminum and hope to do some range testing soon.
For Plain based pistol boolits I ESPC and use plain based gas checks made from soda can using dies from Pat. Most of my pistol loads aren't needing PBGCs due to velocity but I did notice tighter groups with checks. Besides, flat black boolits with shiny aluminum checks look kind of cool. Some guys form the checks so you can see the can label, but I prefer the coated inside of the can showing.