I have a Z3, Z5, and 2 NXS. It may depend on what type of hunting you do as to which one is more suitable to your needs. The Swarovski are around one pound while the NXS are two pounds. If you are looking to stay light weight go with the Swarovski. Either Swarovski will get you to 5-600 yards depending on caliber and elevation. The Z3 will give you 42 clicks of adjustments while the Z5 has 52 clicks. Z3 no side focus while the Z5 does have side focus. If you will be hunting in thicker woods where quick shots are more likely, you may want the Z3. More open and further shots with time to range, dial, and focus go with the Z5. Either way if hunting in low light situations, consider the 50MM and 52MM objective for better light transmission. Get the 4W reticle for wind adjustments and get a custom turret to match your ballistics.
I also find the parallax adjustment on the Swarovski more forgiving than on the NXS. It takes me more time to dial the NXS "just right" vs the Swarovski. I have found that if I am off a little bit it with the Swarovski it doesn't affect my shot as much as the NXS.