I always buy my Prescription Glasses online. In fact, I recently purchased 24 sets of glasses. They had a sale for single vision glasses, 2 for 1. The glasses were mostly for $8 per set, so I got most of them for $4 per set! It cost me about $110 for 24 pairs of glasses, including shipping. Plus...... the service was great. I had a slight problem, and they fixed it right away with a refund!
I don't like bifocals, so the many different reading glasses allows me to have them all over my home, in my pants' pocket, and in my truck. A number of the glasses were experiments, where I changed the Sphere to provide different levels of magnification. I wanted to find the "perfect" glasses for me, and I did it by experimenting with the Sphere!
So...... I got numerous reading, screen, driving and all-purpose single vision glasses at a fraction of the cost of going to a brick and mortar eyeglass shop. I've had them for about a year, and they are GREAT! I love them. If I get tired of a particular style of glasses, I just reach into my eyeglasses and select a different style for that day. I LOVE IT!