Mike, I don't buy many flies, but have purchased some from Orvis (when they have a sale) and Rainy's, and have been very surprised & pleased with the quality. IMO, those like Orvis, Umpqua, or Rainy's will have good quality because they go to the lengths necessary to assure they get good quality. They may even have exclusive factories that only produce their flies. The average shop, who is simply buying from off shore factories may not have that luxury, or may be basing fly purchases only on the price they pay, so quality can vary.
IMO, I tie a much better fly than what I've seen from Orvis, but only because I'm tying to meet specific needs, and they're following a standard pattern. You'll likely find this with most mass produced patterns compared to "custom" or limited production domestic flies. Of course in most cases the prices reflect the difference. None of the big fly producers flies are "cheap" in price, but for the prices being charged IMO, you're getting what you pay for, and same with flies from many domestic sources.
Personally, I won't pay the regular prices that Orvis or these others charge, only because I don't have to and can tie them myself. Those I have bought were on sale (& cheap) & bought to add to what I was tying for a trip.
You would be hard pressed to find a better source than Jerry, but nothing wrong with fill in's from those name brands!