Do they both exhibit the same durability?
If you speak to swaro directly, they will tell you the Z3 line was never intended to be on heavy recoiling rifles. I ran one on a light weight 300 wsm with no issue though. The Z5 has much better internals for heavy recoil. The glass on the Z3s and 5s are unreal. I still have not found glass more pleasing to my eyes. 3-10x42 gets my vote every time and the 4A reticle is the best for hunting. No way you would be unhappy with that setup.
