Fogging in a scope is unacceptable and I'd consider it a defect. Simmons has a lifetime warranty and I'd get their opinion on fixing it. Simmons might replace it with new and if you wanted to go with a different brand you could sell the Simmons as new.
For power on big game in the 200yd range, 2.5-8, 3-9, 3.5-10, would all be equivalent. I generally try to match the scope quality to the gun quality, if its a $500 gun put a $300-500 scope on it, $1000 gun put a $800-1000 scope on it. Most of the deer I've taken in the last 10 or so years have been from my blind and I've yet to take one out of it under 200yds. The gun I've used most is a Sako 243 with a Leu 3.5-10. Last year pic is below at 335 yds and nowhere near the limit of the scope capability. A bunch of years ago before I put the blind in I was making the reverse shot of this pic. Walking out exactly where the deer is laying I saw a very nice 8pt to the right of where the blind is now, because I was walking I had the scope down on 4x and in my haste never cranked it up, didn't even realize I was on the low end until after the shot. That ranged at 347yds.
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