Re: Ziess ??
The mk4 is a heck of a scope. I am partial to the original mk4's but they cost as much as a NXS. The deal is, if you want a scope that is lighter and more compact than the NXS yet want the quality of glass, bullet proofness of construction, reliability and MOA travel that the NXS offers, the original mk4 is a very good choice.
For the budget minded or if you want a variable power, the newer mk4 will be a great choice.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.