I've got two. A sport model (with IR) and an endurance model. The lower end stuff like the sport models are decent optically, but nothing to write home about. I would hazard to guess you could put it on a 30 cal centerfire rifle and it would hold up just fine. As you get into the more expensive models the glass gets much better. I think the glass on my endurance model compares favorably with a Nikon prostaff I have.