Here is my take on this. Take it for what its worth.
I have both a Leupold 45x comp, and a NF 42. I like the Leupold, as it ergonomics are second to none. The Leupold is a very attractive scope, as well. Lower profile and sleek. However my NF does have better glass, and this is how i know so. I was shooting out on my farm a few weeks back. I was shooting just 200 yards, but the sun was on its way down, and shinning in my face. This doesn't make for an ideal situation while trying to look through a scope. Mirage was bad. Actually real bad. I was shooting prone with two different rifles. One with the NiteForce, and the other rifle had the Leupold 45x. I had a real hard time shooting the rifle with the Leupold, but the rifle with the NF was much easier. I simply had a hard time seeing the target with the sun the way it was through the Leupold. Now with this said, and under ideal conditions, i like my Leupold best. I personally think the NF has better glass, or better whatever, but i do like the Leupold a little more. I hate having my parallax adjustment up front on the bell, like the NF has. I think that is a real set back, especially for f-class. You would have to come complexly out of position to make an adjustment on the NF, while the parallax is right were it needs to be on the Leupold.Again this is Just my take, and experience. It isnt worth much but it didn't cost you anything either! Lee
