I ordered 3 pairs, one for reading, one for distance and a pair with Transitions lenses.
I live in Canada, so my first impression was clouded by the lack of a decent shipping option. It took longer than I would like to receive my glasses.
When they arrived I could immediately see that the pair with Transitions lenses was a bit wacky. I couldn't put my finger on what was wrong, but I just knew there was a problem.
So I went to my optician who graciously tested the lenses for free. He found the left lens was either defective or the astigmatism was improperly corrected.
My optometrist said this type of issue can happen and wasn't really uncommon in the industry. He didn't think it was a commentary on Zenni per say.
When I called Zenni to report the issue, they insisted on me shipping the glasses back by regular mail (approx. 10 days), then they would perform their own tests (approx. 14 days) and then replacement glasses would be remade and shipped by snail mail (14 more days). The whole process threatened to take more than a month, by my estimation.
I wrote a complaint in their customer survey and thankfully someone in the customer service department took pity on me and decided to trust my optometrist. They agreed to remake the new glasses immediately.
My new glasses arrived in approx. 10 days and they are great.
This is my way of saying that I think Zenni is a good company, they make an excellent product, but they are not exactly geared for the Canadian market.
If you're in Canada, expect slow delivery and be aware that you might need to be a bit insistent if you have a need for a replacement.