I’ve had 39 Dollar Glasses’ 1.74 index for 2 years and am very happy. Before 39DG, I ordered Zenni’s 1.74 (in almost identical lens dimensions and effective le

I’ve had 39 Dollar Glasses’ 1.74 index for 2 years and am very happy. Before 39DG, I ordered Zenni’s 1.74 (in almost identical lens dimensions and effective lens PD). The lenses on Zenni’s glasses were much thicker than any I’d previously had, and than 39DG’s subsequent pair. I don’t know whether Zenni mis-ground them or what. I’ll gladly reorder from 39DG though.