Isn't this all rather peculiar? A very great number of Pi's have been sold, with considerable publicity. Lots of people are using them for all sorts of interesting projects. If there had been failures on the massive rate reported from Scranton we would certainly have learned about it. Which suggests that there is some specific local problem. So the logical solution would surely be to find out what that problem is rather than just to discard 4 (or is it 5?) of them.
Philip.