I like to keep things simple as possible. I refuse to use apps and calculators while on a hunt. Custom Turrets have there place and can be efficient if made correctly. That being said, I would not burn a turret until i have verified everything which for me would be many rounds fired in different conditions and distances. Kenton makes turrets with Mills or minutes and custom yardages all in one, which I would prefer. My advise is shoot and write everything it down on paper. Write down every thing from conditions to rest used what direction your shooting anything you can think. After a dozen or so trips out, if you see consistency in drops make a turret for it.
After reading all off these (excellent) posts and recommendations, I have been thinking that the simplist solution would be to "prove" my impacts at 100 yard increments, then make my own markings on the turret....what do you all think?