The replacement lenses are a great option when you inevitably get some trail rash or they get buried under your gear. Scott’s lense swap can have you a little frustrated(hence the 4 instead of 5 star). Take your time and don’t force it to avoid breaking the tabs. All that frustration is worth it in the long run. Once these lenses are installed, they’re solid in the frame. I’ll take a bit of frustration in install for safe and dust free eyes. There’s faster swapping lenses but at the expense of risking the safety of your eye balls via cheap inserts and ridiculous and dangerous magnets. Your eyes are important, protect them with US made, quality goggles. The photochromatic lenses are a GAME CHANGER for changing conditions and those day rides that shift into night. A bit of warning. The photochromic lenses, while game changing, are much more prone to scratching over the traditional options. In order to change with light conditions the plastic is a bit softer and prone to scratching. Extra care is needed when cleaning. Think water/windex and a microfiber instead of your dusty riding jersey. All in all, very satisfied with the replacement lenses and the goggles in general.