[Arran]

 What justifies the price? Absolutely nothing but audiophools thinking that an EL84/6BQ5 made in a Phillips owned subsidiary, in Britain, using Phillips machinery, manufacturing Phillips designed tubes to Phillips manufacturing specs, with a label saying "Mullard" in water soluble paint rather then "Phillips" makes them better tubes. So whether the label on the tube says Phillips, Valvo, Mullard, Rogers, or Amperex, (sorry can't remember the name of Phillips' French tube company) they are all the same tubes other then the label and the box. The only reason why people think that they are something special is because a lot of classic HiFi manufacturers used them, and that was because Mullard probably offered them for a cheaper price then RCA or Sylvania would have, and offered to print their name on them like those EICO branded 6BQ5s. But a refuse to believe that because a tube is made in Blackburn, England, rather then Eindhoven, in Holland, is better when it's the same company.
Regards
Arran