You think now you'll only ever want to get to 600, then you'll get there and suddenly it's not far enough. Don't pidgeon-hole yourself outta the gate.
Spot on. In one day I went from shooting out 400 yards to 425 then to 700. Just by twisting a m1.
My experience was similar. I had an M-1 on 1 rifle and several B&C reticles. I got the B&C stuff sorted out in about an hour then those rifles sat while I fiddled with the M-1 topped rifle. It took me about 30min to realize that the B&C had buggered me outta the gate. They were all gone within 6mo.
A turret, a good drop chart, and a notation regarding duplex subtension has taught me way more than any extra hash-marks or custom dial ever could.