Nikon prostaf 3x9 BDC about $130
I have a few hundred rounds through my upper with ought any problems.
I have also dropped the rifle and scope out of my 12ft stand one morning deer hunting with no ill effects.
I would say my best experience with this scope is the BDC. With factory ammo a 16in tube 1in high @ 100 the second circle down is exact @ 200yds. I took a doe just after Christmas this year at exactly 189yds.