I expect the Mark 5 is a great scope, but I hope I don't have to open the cellophane on this one. ;-) I had a Mark 6 prior, nice scope, but it broke and Leupold replaced it with this one. (Fantastic customer service) The silver lining was it took long enough (7 months) to get this scope on warranty and I bought a NX8 & mounts in the meantime and like it to the point that I am not compelled to tool up for a 3rd diameter of mounts (35mm)...so, I figured I'd take a run at selling it. ...fingers crossed... thanks for stopping by.