I will happily defer to you on the specific subject of Volpe, but I've heard from more than one Neapolitan in the trade that Rubinacci does the best work in Naples. The degree to which that is true is another matter--but my point is that one hears just as much good as bad from competitors, and to my mind, the former is more telling than the latter.
Not trying to be defensive on Volpe, but I will stick with what Marco says.
Noone with whom I talked to could say that Rubinacci is the best in the city. Comments were different from quite negative to moderate. It was in the context of asking who is/was best tailor/sartoria in Naples. I have never heard that Rubinacci is best of the best. Among best definetely, but not on top.