That's a tough call, either quality glass of the SWFA, or more magnification of the Weaver. I plan on putting the Primary Arms 4-14 FFP on my 6x55, eventually I'll get a 20x SWFA Super Sniper for it. For 1000 yards, quality glass beats magnification every time, especially when you start to add mirage to the mix. The clearer you can see the target at less power, the fewer problems you'll have with mirage. Given your two choices, I'd pick the SWFA.
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