I got a turret for my 3-12x42 and for my 4-16x50 Monarchs. Having done that, I do not recommend this route, unless your bullet / load will never change, and that you somehow have the same magically consistent atmospheric conditions every time you hunt or shoot.
The Nikon "spot on" store got my credit card flagged for fraud by posting multiple duplicate transactions. It took me 3 weeks to get a replacement credit card. It took intervention from Bart to get the matter resolved.
I no longer use the turrets, the whole exercise was a waste of time. it has been popularized on TV shows where the people making the video can afford to literally carry dozens of custom turrets and pick one suitable for the hunt conditions / video footage. Both of my scopes now have the standard turrets back on them. I have a drop chart taped to the left side of the rifle stock, and I can replace it under different atmospheric conditions for essentially nothing or 10c for a printed page if you want to split hairs.
Nothing is ever constant. Your rifle barrel performance changes with time, you may have to use a slightly different bullet due to shortages in the market or bullet rationalizing efforts like at Hornady. or someone introduces a new bullet that you "gotta have" and just like that your turret investment just went up in smoke.
Be a savvy consumer and recognize that the people pushing the custom turrets are the same people making them or selling them. Just stick with portable drop charts and regular turrets. keep your money for reloading supplies or the new barrel...