10 months after my last eye exam I noticed a vision change in my left eye when shooting pistol. My right eye, the one with the bionic lens, still had good iron sight focus, but the left eye distant focus had degraded. However, even the right eye has shifted slightly (again). Given I have three pair of shooting glasses I'm grateful two pair use Rudy Project inserts so the cost to change the prescription is reasonable. The Hunters Gold, which I like for certain conditions, I'm not going to replace. Fortunately, this gives me a good excuse for missing some of the distant targets at old-man speed. This is a cautionary tale for the young that if they intend to shoot into their 70's to budget for frequent changes in eyeglasses