Both are excellent scopes, both have great glass. I run a Z5 on my ultralight 30-06 TIM as it's light & the 18x top end is what I wanted & also run a couple of 3-15 VX5's & find em a really nice piece of kit, Leupold certainly did their homework & listened to what people asked for.
Z5 is a great lightweight alrounder, the 4W reticle I really like, it is quite long however & not the best scope if your'e a real rough bastard, the 13.25 moa travel is a bit limiting but plenty for most hunting situations.
VX5 is slightly heavier but more robust, great eye piece - eye box & the twin turn turret works great, their windage plex can be a little compressed / busy.
From my experience - If you do have a problem the after sales warranty service in NZ is better from Leupold ( NZ Asia ) than Swaro
Your'e be happy with either, just pick one that suits you.
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