Not had mine very long so still sorting it out on my S410. I measured out 25yards and at X50 magnification found that the focus snaps in and out precisely at the mark on the sidewheel. Same at 60yards, and using the first reticle line down from the cross and half a reticle to the left for windage (at the time) I was reliably hitting the target centre. I like the NATO reticle as it is clear and uncluttered with thin lines rather than dots. I zeroed mine at 17 yards and rarely sight above the cross which is a point as there are no reticle lines above, but easy enough to extrapolate. So far I have obtained excellent results as I find the NATO reticle easy to use. I too would appreciate any comments from more experienced users.