I have the 4-16 SFP PST and I can see clearly at about a mile. Obviously not shooting at man size targets but it's not out of the realm of possibility. The Viper is a fantastic scope and I would go for it. Nice glass just becomes a way to show off how much money you make after a certain point...
I feel bad for this guy, I'm not qualified to answer for his specific question but someone extend an olive branch lol. And everyone likes to feel tacticool every so often. You're just jealous because he's getting paid to do it.
I have an SPS Tactical chambered in 308 that I just picked up today and now I'm hunting for the round that the 20" heavy barrel likes best. It's all stock and I'll get the bell and carlson a3 soon then it's probably done.
Back to the question, what does this rifle normally like to eat?