Most people don't like to shoot, and most people that shoot generally aren't twisting knobs. When you start spinning knobs up and down and working over the springs in a scope, that weeds out the junk. I thinking plunking holes in a paper target at 100yds is boring. Therefore I shoot distance and "use" the scope. Most scopes just don't last in that application. Comforting to hear SWFA do, especially considering their cost!