has anyone ever had any issue with the 3.5-15x tubes being two-piece. I just recently had a rifle with one go crashing to the ground on top of the elevation knob. Scope seems fine and turrets seem to track fine. I haven't even shot the rifle yet. I know nightforce is a quality product, I'm just curious if any issue has ever arisen out of this i.e. kinda like some say USO has tracking problems or some scopes illuminations don't work properly. Two-piece tube designs aren't exactly praised but Nightforce definitely has a good reputation and I'm just wondering if the design quality control of the 3.5-15x is right up there with the rest of their scopes.