Best epoxy primer

As far as the gun discussion goes. I have had a Devilbiss FLG3 (they are up to FLG4 now) Finish line gun for several years now. I have done some awesome paint jobs with it. I never had any problems with it no matter what I sprayed. I have recently retired it to primer only since buying the As far as the gun discussion goes. I have a Devilbis Tekna Copper gun. But I HIGHLY recommend the Finish line.