Some charts are very generic and do not match real measurements at all. Even big and famous brands sometimes send generic replies that are not very helpful. I do not trust only the star rating, I like to see detailed photos and longer comments.
If anyone is interested in real user experiences, I sometimes write short notes about the shops I test.
You can find one of the pages here:
click here
(https://igiasu.com/2026/01/17/clarity-perfected-the-ultimate-guide-to-mens-glasses-reading/)
For things that I use every day, I prefer to pay a bit more if the quality is stable. The same is true for metal versus acetate frames for glasses. This is why I like reading and posting on forums and community websites. Good stitching usually means the item will not fall apart after one or two washes.
Just sharing my personal feedback.