I have the Leupold, have used it on several air rifles and rimfires, and it is a very good scope. My only complaint is the one shared with all AO scopes. If you need to do much focusing, the AO is cumbersome compared to a side focus, which is the only type I will buy now. Although I have never owned the Nikon, I have found their scopes to be the Sony of the optics world, maybe not the best, but a great value. I have found the difference in brightness, clarity, etc. is usually not a problem except under the most adverse conditions; i.e., poor light. I expect you might find a similar advantage if testing under very cold or wet conditions, but my 68 years of experience have taught me at least one thing, that is whiskey sipping weather, not shooting weather.