I have three 6X42's mounted on hunting rifles. One of them, on my "Big Stick Special, .25-284" killed a big running buck that got up only 20-25 yds. from me. He made it almost 50 yds. before the second hit put him down for keeps.
Two of mine are the older M8's. One is the latest FX3. I really like the dead nuts on finger tip adjustments, and really appreciate the super hard Diamond Coat2 coatings on the FX3.
All of them have lots of eye box, the fore and aft leeway I really like when I'm in a hurry to shoot. E