If it were me I would try to return the scope and get my money back, after all dents are a little more than "light ring marks". That being said I have heard of scopes that have been damaged still holding zero and working fine. You could try it out before you make a decision. Still, I would first try to return it . It's possible that it would work ok for a time and then go south when you least want that to happen. I am not sure if any scope company would honor a warranty on a dented scope.