I have to honestly say I was not sure I would keep the Jawbone when I ordered it as I was not crazy about the frames( I am a runner) I received them in 24 hours typical of Zappos!! I ran 9 miles with them in 40 degree weather and the lenses fogged up for a very short period of time, however, nothing that bothered me as they became defogged quickly..and these are not even the vented type. The style is really cool, the lense clarity is second to none and the lense swapping is easy. I am incredibly impressed with these glasses and appreciate even more the service from Zappos. By the way, the additional yellow lenses are great for night running and driving. Thanks.