I have a bolt gun with everything cerekoted. the bolt, lugs, extractor etc. every surface that is not the chamber, firing pin, fire control surfaces or inside of the barrel is coated. it is smooth, looks sharp and provides good corrosion resistance. a few spots on the bolt lugs show some wear, but it is small areas of exposed metal and the cerakote holds a light coat of oil very well so even the worn areas are protected.
I like it, I would gladly get another rifle cerekoted, but as others have said, verify it is well done or that the areas to be coated are not critical fits. I would do my own barrel if I could, but I would send the action off to a professional, then again, I might have rattle canned a shotgun and might rattle can my 3gun AR soon