Just got back from the range, mounted a reflex sight on my S&W 686 6" this weekend using the factory drilled/tapped mounting holes and a Weaver mounting rail. WHAT A DIFFERENCE! No more trouble trying to focus on the sights and the target at the same time, and 2" groups at 25 yards, with 158 grain SWC's. It's not even an expensive sight, a 80$ Sight-Mark unit. Now that I have tried it I will be looking to add reflex sights to some of my other S&W's and Dan Wesson's. If you have thought about, it give the reflex a try.