Progressive lenses require accurate measurements for the positioning of the "sweat spot" in each lense. This is done by a human when doing in a doctor's office.
They line up each pupil and mark it on the sample lense of the selected lenses. This is impossible when ordering online. They guess by using an "average" measurement. Unless you're "average", chances are the sweat spots won't line up with each other, meaning if you find it in one lense, you probably wont be lined up properly in the other.
This is my personal experience.
Disappointing to say the least. I won't try this again.
Product or Service Mentioned: Glassesusa Eyeglasses.
Reason of review: Bad quality.
Monetary Loss: $200.
Preferred solution: Let the company propose a solution.