I have been looking for a set of glasses like this for a LONG time. I've owned a variety from most major sport optic manufacturers, and this is the first pair I've been totally happy with. The biggest thing for me is the rimless design above the eyebrows. When descending in the drops, I don't have to compensate for looking around the usual rim that you find on sunglasses. In the past, I would either slightly pull down the glasses or have to really kink my neck to get a full field of vision. The lack of rim on the Pivlocks is a fricken miracle. The lens swap out is so fast and there is no worry of scratching the optic like on other designs. These vent exceptionally well and the only time they fog is in the elevator after my commute...but as soon as I start walking, it clears up. Highly, highly recommended. Especially if you have a big fat face like mine!