Walkerwear,
I'm not sure you are going to get an answer on that one, and if you do, a single person's experience is not something that can be easily generalized to everyone. Of course, if we could get 10 or more people responding, that would show us a definite trend of what is good and what is better.
Also, be aware that you may not be able to take frames you bought elsewhere and get the lenses at Costco. They used to do that everywhere, but I've heard reports that some locations are not. Usually, there is around an $18 charge to use frames that were not bought at Costco, supposedly to cover the cost of making a new template for the lenses.
There is a
detailed thread about the Costco multifocal lenses, but even there I don't see much, if any, feedback from someone going from an expensive pair of progressive lenses to the Costco lenses. Also, single person reports are not all that useful in my mind. Everyone is different, especially when it comes to progressives it seems.
If you do wind up getting progressives from either Costco,
Walmart, or
Sam's, please share your experience with us all here!