Decent scope - Sightmark 10-40x56mm Triple Duty Tactical Rifle Scope

After two trips to South Dakota prairie dog hunting I decided that I have spent enough time with this scope to write a review. The scope is a decent scope for the money. I bought 2 of them for two rifles that I had built. The glass on mine is clear at lower powers, but when you get above about 14 or so zoom , it gets very blurry and you cannot see out of them. But the mirage is bad on the prairie so I spent most of the time at around 12. No matter how you adjust the knob on the side, it doesn't help. The good is that the scope returns to zero and is repeatable. I was very surprised for a scope that cost around 300 bucks. All in all not a bad scope, I have contacted sightmark and I will see if they will replace them.