The way you have worded this question suggests that you understand that there is risk involved, so let’s define those risks:
Visual
Progressive lenses, moreso than any other lens on the market, rely on precision measurements to ensure optimal visual performance. The height at which the distance, intermediate, and near viewing portions of the lens sit varies based on your anatomy, the frame design, and the interaction between the two. Without measurements being taken while you are wearing the selected frame, the correct positioning of the various powers in the lens and, in turn, your vision are nothing more than a guess. In fact, some online retailers will not even attempt to provide progressive lenses based on these facts. Kudos to them.
Financial
Most people who consider online glasses do so because of cost and that’s 100% OK. However, the consumer needs to know when comparing costs if they are comparing apples to apples. For example, if an online company is offering anti-reflective lenses for $25 while their eye doctor’s office quoted $100, the consumer needs to know if the exact same lenses and technology are being compared. A plastic lens with low quality anti-reflective treatment will not perform the same visually or from a durability standpoint as a Trivex lens with Crizal anti-reflective technology, but will be much less expensive.
So whether or not you should take a “chance” with online progressive lenses, depends on your understanding of the above and how much money you’d be out. Is there a chance things could work out well? Yes. Are the chances greater that they won’t? Yes. Do you deserve better than a “chance” that you’ll see properly? No question.
I definitely agree… it comes down to quality. Right now there is no government entity that is monitoring or policing the online glasses industry (even though they should be.) Even if there were more scrutiny, the precision measurements necessary to fit a successful progressive is not available online and most online stores are just guessing. Also the financial side of it is worth stating that you are rarely comparing apples to apples when ordering online. There are many many different anti-reflective coatings available on the market today and the cheaper the price tag the lower the quality almost 100% of the time. In addition there are many different types of progressive lenses, types of plastic, types of photochromic, etc …. how do you know you are getting good quality when you don’t even know the brands to be buying?
What is the old saying? BUYER beware! Couldn’t be more true when ordering from a non-professional for something so important as your visual outcome. Would you rather trust that what you are getting is a good quality? or would you wonder if it was made to standard , to your prescription? A recent study in the journal of OPTOMETRY found that nearly 50% of all online glasses orders were made incorrectly or didn’t meet standards.
I’d say they would have to be very very cheap for me to consider it, and then I would have to realize that what I was ordering was the cheapest thing possible. Expect low quality and realize it might be just money thrown out the window.
I also agree with the other commenter. There does need to be more regulation on the issuing of the “general one size fits all” glasses that you see for sale in drug stores. Also I am amazed that there are not more cases publicized about the things that can go wrong with laser eye surgery. That is also something I think needs to be looked into