Both are great scopes. I have two Leupold 4.5x14x40?s AO, one Vx3I long range 4.5x14x50 30mm tube and two of the ones you mentioned. Also have the Ziess V4 4x16x44.
The 40mm Leupolds are great for a hunting rifle......light weight, mount low on rifle, clear, great eye relief and quick target acquisition. I like the AO on the 40mm ones and side focus on the LR 50mm...great for aging eyes. I don't like the 50 mm objective on the VX3i, it has to be mounted to high for my liking..... took it off after one trip to the range. All of my Leupolds have the CDS or M1 style turret. The CDS is great for hunting, low profile, track fine and zero stop. The M1 style doesn't have zero stop, but works fine.
The ZEISS V4 is 30mm, has side focus and a great hunting/target turret with zero stop. It's a fine scope for the price. Good glass, turret and side focus work great. Eye relief is good, however, I seem to have quicker target acquisition with the Leupolds, but that may just be me? The ZEISS is just fine though and I may buy another one. It is heavier and bulkier than the Leupold scopes that I have.
Hope this helps, best of luck.