IOR Valdada 10x42 fixed. I owned one for six years and ran 2000+ rounds of 6.5-284 under it. It was a truck gun, it often lived in the floor board or tractor without a case, just Butler Creek flip covers. Dialed it to 1900 yds and returned to zero multiple times. The number of 400-800 yards shots was a lot, and never once did it lose zero. It has a steel tube, great glass, covered turrets, etched reticle, huge field of view. I sold it with the gun and the man who bought it has not re-zeroed yet and he has owned it since 2009. I know they get a bad rap from some folks but I had excellent service from mine. I did replace it with a Nightforce NXS and it has been flawless as well but the glass in the IOR is better IMO.