That choice tells me you're not too concerned about weight. If that's the case, you're far better off with a first-focal plane scope and some knobs and a matching reticle for pure long-range work.
If you're going with a second focal plane scope there is little to no advantage of having that level of magnification and a holdover reticle. You won't be able to use the reticle at anything other than one magnification setting. Anything higher than that is wasted.
I have five of the 3-9 conquests with the RZ-600. At 9x I can use them on everything from a .260 to a 300WSM by manipulating the zero range. The important part of that is that I can turn the magnification ring to a hard stop at 9x without looking and know I'm in the right setting for my reticle to work. hunting timber? Magnification on 3x. See an elk out in the meadow at 450y? Turn to 9x without taking your eyes off your bull and shoot. If hunting at 600 yards meets your desires for long range then consider that as an option. If you want to go farther than that you should consider a dedicated LR scope with a reticle in the first focal plane and matching units knobs/reticle.
