years ago all of my iron sights were replaced by glass, in fact, I completely got rid of my muzzleloaders because my eyes just cannot use the irons. In the last year I have got a fiber optics and hunted for the first time in 20 years without a scope. Up to 75 yards, in the woods, they are great. Young eyes may use iron OK, but for me the fiber optics rolled the clock back decades.