I have been looking at a 6 inch 586 or 686 to shoot Distinguished Pistol (PPC) matches with. I have noticed that the majority of those for sale have the adjustable rear sight with the red ramp front sight but a few have the adjustable rear with the patridge front sight. Are these patridge sight guns a lot less common? Any idea of the percentage of guns made with the patridge sights? Should they bring a premium?