We joined Costco just to get my husband's glasses. The price is good, but the REAL Reason we got his glasses there is because of the WARRANTY. If anything and they mean ANYTHING happens to your glasses, they will replace them FREE. So he buys one pair from his RX then after about a year, he buys another pair. Since he works outside and around all sorts of stuff that scratches his lenses we felt the WARRANTY was just so worth it. Our Costco will honor a RX for two years. So this is working out great for us. We just went last night and turned in one of his pairs to get the lenses replaced. And YES you have to join Costco to use the Optical dept.