Everyone has their own opinions. And I do not doubt that sometimes there is a bum pair from an online supplier.
But, I have known many people who have received bum glassses from a local glasses shop.
The difference being that it is probably easier (or not) to get satisfaction from the local shop.
having said that, I have pretty severe myopic (nearsighted ?) eyes. I need pretty severe correction. And, I need progressive lenses.
I have five pairs of progressive glasses from GlassesUSA (two Rx sunglasses and three everyday, get around glasses). I am pretty tough on glasses. I tend to sit on them, roll car tires over them, the black lab dog sometimes ends up them.... Anyway, other than my self-destructive habits, I have had no issues with these glasses whatsoever.
Have ordered one pair from GlassesUSA for my mom and she has had no issue with her progressive lenses.
Most people I tell about ordering online (including my wife) have severe doubts.
Three friends who decided to order have all been satisified. YMMV, but considering you save a great $$$$$ of money (and I do mean a great deal of $$$), it may be worth it for you to try it.
I was very surprised my wife decided to try it this time, but we would have lost the cash if we did not do it, and the pairs she ordered will both be back-up pairs, so she did not risk a lot.
I will be very interested how satisfied she will be in a week or so, but I suspect she will very surprised -- in a good way. If not, I will hear about it for a few weeks....
Go google zenni. Also, many threads on this on these very same budget disboards. Search for them. If I remember right, Zenni came out on top and tons of people recommended online orders. But, as mom said, if tons of people jumped off a cliff....