I just got the 4-12 in the mail, great deal!! Half price for a quality hunting scope!!
PLUS: If you go to Nikon website, they have a program that you enter which Nikon BDC scope you have, and what EXACT ammo you have, and it will print out the 'dope' for the BDC reticle - specifically tuned to that set up!!
You print that dope out and tape it to the side of your stock and you will know the exact yardage of each dot in the BDC.
PS: Remember the impact points of the BDC circles CHANGE depending on what magnification you have the scope set to. POI at 4X vs 12X can be quite different, so knowing that dope is critical if you are gonna shoot this scope long range.
http://spoton.nikonsportoptics.com/spoton/spoton.html#:4