I have several tang mounted sights from Montana Vintage Arms in Montana, and they are of the very best quality available anywhere in the world, in my opinion. They have a Vernier scale that is easy to read and very repeatable, which is critical. They are, as one would expect for the best, relatively expensive. For example, owing to the rate of exchange between USD and CND, I have almost $1000 in the rear and front sights on my Sharps. But worth every nickel to me.