[DDS]

One thing that nobody has mentioned in this cost of factory flares discussion is profit margins. The OEM units go from the elf in the Black forest, to Porsche, to Porsche North America, probably to a dealer, then to PP or whoever. That's a compounding 20 points per transaction at the very least. You can bet Porsche is marking it up lots more than that. (REad the issue of Panorama where they boast about their profitability at the PCA banquet...) Porsche is probably paying $100 for four. There's no reason to assume that it couldn't be done for $500, as Malfrog and others suggest.
In the past, poor access to information (by customers) killed small enterprises serving far-flung niche markets, so a network like that was a necessary evil. The internet is a boon to cottage industries like what I hope Frog starts.
Like Rich I bought 'glass flares and they were awful. In the end they'll be fine, and I'd do 'glass again, but only because I refuse to pay for a "pedigree" in a stamped steel fender.
Go Frog!