make sure you handle them first. I have quite a few leupolds, and only one nightforce. I have the 5.5-22 NXS, and love it, but...it is heavy.
if you are looking for a light carry gun, i would personally stay with the leupold. If you want more of long range setup then get the nightforce. I love both, but the nightforce are solid.
that being said, I carried my NXS up to 12,000' hunting elk in CO, so take it for what it's worth.
have fun, they are both great scopes.