AS far as durability, i've got a 2-7x32 BSA "air gun" scope that i have used on my .17 NEF. I also used it on my CZ.
So far, it's been really excellent and I'm impressed with the finish--for $50 it even has metal screw in lens covers! The clickstops, so far, track perfectly. I have used it for silhouette and it cranks up and down for distance without a hitch--so far.
I keep saying 'so far' because I haven't dragged it behind a truck or anything yet. And I've heard other folks shriek about BSA. Maybe I;m lucky, but I'd buy another one.