My name is Josh Quigley and I have been wearing the smith IO for two years. I know a lot of the details about the goggle. The Smith IO has developed an anti-fog technology, and with the super easy interchangeable lens system, it is really a no-brainer. I have competed in a lot of contests throughout the past few winters and I have worn the IO the whole time! Smith offers a variety of lenses for every condition out there. My favorite is the blackout lens. I like this lens because it looks really cool, but besides looking cool, this lens is mirrored and keeps the sun out of my eyes so there is no distraction or glare. I am in love with the Smith IO.