I have a nice .338 WM I am adding a new scope to. Done my research and determined that a Leupold VX-3 3.5-10x40mm is what I am looking for. Leupold has the free CDS dials if I pull the trigger before 12/31/10. However, I am going back and forth between CDS or just getting the Boone & Crockett reticle and calling it good. My .338 is a hunting rifle with LR for me defined as 300+ with a max range of 600. Or course I'll need lots of practice with the new scope, but wanted to let you guys know the intended use. With the CDS dials you send them your load data and they make you a custom dial. I often shoot at low elevations and hunt at high elevations. What is the impact of elevations on my groups and how can I adjust if the dial is set for a specified elevation? Any and all info would be appreciated! Thanks!