On third set of these--they hold up well over time, lasting about 1-1/2 years with daily use/abuse (usually due to lens scratching.  Distortion free and nicely polarized.  If you are a "flip-up" dork like me, these are for you.
UPDATE--11/10/16: had returned one pair of these under "Lifetime Warranty", due to material failure at bridge tilt mechanism--think that pair was about 4 years old; required $4.00 S/H + postage, so no real net gain, but thought would be nice to have backup pair.  Was returned to sender (me) with "Expired Forwarding Address"--guess should not have bothered with warranty, as lost the shipping $ ($4 check was returned unopened).  Still give these 5 stars without any warranty, as they do hold up well.