While had Rydons for years, these inserts were an improvements over the prior full metal frame as rattle eliminated. Then this weekend in a major accident, including a broken collarbone, and thought the glasses were history as the force left them in 4 pieces on the trail. Reinserting the Rx Insert lens plus both outer lens (a little scraped to send in for replacement) and adjusting the nose bridge and the Rydons are fully functional. Illustrates why I like the standard lens protecting the Rx glass in the insert. It is nice now that they can put a progressive Rx in the curved design where originally was single vision. A little more difficult to remove than prior, but only remove about 10% of time for comprehensive cleaning, where 90% of time is a lens wipe on the outside and inside with glass to glass sides not requiring as often. The glass to glass feature also allows some economizing on Rx, deleting features such as scratch resistance and other coating, provided by the original lens. Finally, I never have understood paying for sunglasses where marketing is touting the superiority their glass...then immediately discard it and put in Rx glass. An insert is the best of both worlds.