I've had a lot of success using krylon ultra flat black paint as a base primer. It's a nice matte finish that's thin enough to show all the detail. That said, I've had terrible luck using mini brand primers, other than floquil. I'm busy trying to clean up my last batch from having a chalky effect that the primer gave them. It's wierd; I can brush off the most of it by touch. Anyone have this happen to them before?