I have several Mark IV's on various rifles including a 50 BMG which is pretty harsh on scopes but they have all held up well. The turrets are repeatable and positive. Have both mil-dots and TMR reticles. The TMR is more precise when range finding. You should be good to go with a MK4. What power did you choose?
It's to late now but I really think the Nightforce BR scopes shine for target use. I prefer the 12x42x56 model with the NP-2DD for LR targets.