The lenses in these glasses (I have two pair now, one plastic and one metal framed) are very good. Just a small step below the more expensive prescription version I also have. However, I already returned one set of glasses as the ear piece on one pair was falling off &#34;out of the box&#34;. I can see why other reviewers have concerns about the reliability of the frames. Both plastic and metal versions have similar ear piece mechanisms. I will be extra careful as they may be prone to failure. Placing these lenses in a quality frame would be an excellent value and one I would rate higher.