I would go Sightron over the Mk. 4. Don't get me wrong, I love Leupold and use them, but for F-Class you really want 1/8 MOA clicks and target type reticles. You also want as much magnification as you can. Again, I use and love an 8.5-25X50 VXIII but if you're shopping, I'd go for more power. The Mk4 is more of a tactical scope and they lack the really fine target dot reticles preferred by F-CLass shooters.
FWIW, the Mk4's fetch a pretty penny; you could flip it for a NF![]()
Not sure if I understand your post correctly.. are you saying the sightron comes with 1/8MOA clicks?