Do NOS Mullard EL34 tubes last much longer than NOS SED (Svetlana) EL34 ?

Bjesien, is correct on the nos Mullards, they have a sense or ease. In my system it has a natural sparkle to them I’ve found no other can do. I have a class A that can only use kt-120 and kt-150’s so sometimes it’s nice to go back to the Mullard el34 sound. 

$450 for a fx1 is way to high for me.  I bought 4 quad’s of fx2 over time when I noticed prices going up years ago. I’ve been buying used xf2’s that test as new for 1/4 of the price for the fx1 quote you have. I’ve been running the same quad’s in a CJ amp for years with never an issue. I also have quad’s of sed wing C’s from the 80’s that to me do not sound near as good as the xf2’s. Some of the wing c’s have red plated on me, much better luck with the Mullard.