I started this thread so that I don't cause the chrome paint thread to go too far off topic.
Most of our engines are cast iron barrels and aluminium heads. The difference in the coefficient of expansion between the two metals will cause the mating surfaces to slide over each other as the engine goes through heat cycles. I fail to see how silver paint, when it is dry will seal this surface. I use a smidge (say 1 thou thick each side) of silicon sealer only around the oil channels on my copper gaskets and have not had oil or combustion gas leaks.