I have a couple of Vari X-III's and a coupe of Z3's. I have used about every major brand of scope out there. The Leupold Vari-X III do fine. I have a Z3 on a 338 Win. Mag. and a Z3 on a 300 Win. Mag. Both are 2.5-10x50mm. The Leupolds are on a 444 Marlin Guide Gun (1.75-6X32mm Compact) and a 30.06 Spr. BBR (3-9x50mm). I have zero issues with eye relief. As far as contrast, clarity and crispness of image, I'd put the Z3 way out front. As far as low light, all 4 will take you well into "illegal" hunting hours. I can clearly see from right at daybreak until well after sunset. As far as being rugged, I have had no issues with any of these 4 scopes. In your shoes .... Z3.