Sunglasses with lines in the lenses... bummer - Zeal Optics Felicity Sunglasses

These sunglasses are the WORST! They look great and feel great, but no matter how you take care of them, they get lines in the lenses after about six months. I have now sent these back to Zeal Optics at least three times (cost $10 each time, plus shipping), the last time requesting a different style of sunglasses in the hopes that maybe a different lens wouldn't do this. I was sent the exact same pair of sunglasses as a replacement. This time around, I figured maybe it was something I was doing, leaving them in the hot sun too long (ehem... they are SUNglasses...) ... something. But I kept them in a hard container in my purse, which comes inside with me and out of the hot car and are protected from the elements but for typical wear and tear worn in athletic pursuits. Guess what? Exact same problem. Lines in the lenses. It's a shame, because these are such great looking sunglasses at a great price point. I now say to anyone looking for sunglasses: Go buy Smiths. They are still top notch in the field. I can actually wear them and use them and nothing happens to them. Go figure....