If you get a mil-dot, I think the best one's are those that are accurate at 10X. With this system, if you know your target size, say, 6ft, well that will be 2mils at 1000yds which corresponds to 10X on the scope. The cool trick is, if ranging a 6ft target, zoom in and out until it takes up exactly 2mils and your power setting x 100 is your range. So if it takes up 2mils at 4X, then your target is 400yds away. It can also work for 36" targets (Like hogs or deer shoulder to hip) using 1mil instead of 2.