Having double AR applied will definitely make it look better, but I believe, technically less gen like. Also, the outer AR can sometimes be fragile and will scuff easily. Swapping in a Swiss barrel is always advised during a service. Wont necessarily net you a longer PR, but reliability and longevity. I've timed asian and swiss 6497 mainsprings before and the PR difference was only a couple hours, both were +50. The main thing with swapping in a swiss counterpart is for the piece of mind that it should run better for longer.