Albertporter ( and the rest ) funny you should mention the Mullards, and the Telefunkens. I have both of them. So maybe I should just leave well enough alone. You know what they say, " ignorance is bliss ". I was only intersted in the Amperex becuase I had heard that they sound great in my BAT VK5i. But then I also was recomended, the Tung-Sol 5881's and I didn't care for them :)