I bought a MOnarch 3 4-16 x 50mm earlier this year and mounted it on my hunting rifle. I am impressed with the clarity of the glass, the amount of light it allows through (I could see things through the scop 100 yards away that was too dark to see with my bare eyes), and I have only messed around with the BDC a little out to 300 yards and it seemed to be good. Also, my rifle bounced out of my gun boot on my ATV, scratching the scope - it never lost zero. What you need to do is use the Spot On and enter in the details of your cartridge and then memorize what the rings are on the BDC. Thus far, I am impressed and will buy Nikon again.