I am debating between the rapid z reticles, the 800, 1000 and varmint. It is going on my 7stw, and realistic ranges of 500-600 yards. I like the idea of the 6.5 x 20, but the z1000 reticle seems way off when I plug the numbers in, i realize it designed for the .308,but it looks like the varmint would work just about right out to 600. Or would the 4.5 x 14 with z800 be a better choice? Any input on either of these would be greatly appreciated!