My son had his eyes examined in Aug, buy Feb he was complaining that he couldn't see very well. His lenses were treated with scratch guard and had a cloudy film which could never be cleaned off. When he went back to get them fixed, since he opted for insurance, he was told the insurance only covered the frames not lenses. So we had him get an entirely new exam, 9 months later. His RX changed for both eyes. The doctor who did his exam was terribly rude and said it's highly unusual for both eyes to change so much - geez maybe it's because you did his exam wrong. Of course our insurance didn't cover another exam this soon so we had to pay for it all out of pocket.