I use the Leupold MK4 scope you are intereseted in for long range shooting. Have the scope mounted on my 308 Rem 700P, my longest shot with it so far is 1030 M. Optical clarity is really nice, the illuminated mil dot is a nice thing to have just in case too. No problems with the parallax adjustment, turret adjustments are all positive ( no mushy feeling ), durable too as I've given it a few bumps so far. The only thing I don't like about the scope is that the turrets are in MOA and the reticle is in MILS, having both the same would be better. If I had to go back in time, I would have got the Nightforce for common turret and reticle units.