I believe you are referring to the "NM" rear sight. I only have experience with the 10-8 sight for the Novak cut. The closest thing I've used to what you're describing is the Yost Retro sight which also has a .140" notch but is not "U" shaped. I love the Yost Retro but I wish it the U-notch of the 10-8. Both make one-handed slide manipulation a breeze. I think the 10-8 "NM" sight is the best of both worlds. Clean uncluttered sight picture, functional, fits the standard dovetail, and works great with a white/tritium/FO dot up front.Any of you folks use the 10-8 U-Notch rear sight. Its the version that looks somewhat like a standard Colt rear.
If so, how do you like it?