I have a Ncstar, on my AR-15, and I have never had a prob. I shoot it at 200 yds., and for me it works, and very accurate. It lights up, and still have the original battery in it. I have had it for at least 3-4 years...
No, I set it, and shoot, only had to reset it once.....have you ever had to dial wind or elevation and had it come back to zero?