I purchased a pair of Western Electric 300B tubes a few months ago. Installed the tubes in an Air Tight ATM-300 amplifier. Before the even initial 90 days was up one of the tubes shorted and destroyed a capacitor and resistor in the amplifier to the tune of $1000 in repairs.
I returned the tubes (within the 90 day warranty period) to the store from which originally purchased. The store promptly sent me a replacement pair of new Western Electric 300B tubes. I installed the replacement tubes in another amplifier (Elekit 8600S, since my Air Tight was in for repair) and one of the replacement tubes was faulty! No music in the channel with the faulty tube, just some crackling and popping noise.
(Yes, the Elekit amplifier worked perfectly with other 300B tubes, and the problem moved channels when the tubes were switched)
I have now returned the replacement tubes for a full refund. I had heard rumors of quality control problems at Western Electric. I will not be buying ANY Western Electric tubes after this experience. Very sad since I really wanted to support an US manufacturer.
-GAR