I have one - the NXS 5.5x-22x-56mm Illuminated (well...all of them are illuminated).
It weighs as much as a cruise ship's anchor, but it is built like a tank.
It has very good glass, but not as good as Swarovski (which is the same price as the NXS).
Shooters use these scopes for 1,000 yard benchrest competitions, so you know the optics must be good.
As for hunting, forget about using it on a mountain gun - no hiking here - unless you WANT a workout.
For hunting purposes, it really is more of a novelty scope.
Zachary