Elrog 300B vs Takatsuki 300B tubes


Has anyone heard the Elrog 300B tubes ? I read an article which mentioned that the Elrog 300B delivers 15% less power than a traditional 300B tubes. Can anyone confirm that it is audible ?

I am choosing between Elrog and Takatsuki 300B tubes. I would prefer the Elrog because it is cheaper and supposedly wonderful but if it really sounds less powerful then I have to rethink.
pani
I've  installed  my replacement Elrogs in my amplifier today .  Needless to say that they sound divine. I hope the cathode resistor swap is the answer for tube longevity in the Frankenstein MK II. Time will tell. 
Charles, 
Hi Charles (and other Frankenstein owner),

May it be that the filaments of the Elrogs are very bright after switching on the amp for 2 or 3 seconds and then the brightnes is decreasing within the next about 5 to 10 seconds?


Mk,
I haven't noticed that with my amplifier thus far. 
I thought I have another bad Elrog replacement tube a few days ago, no sound from one mono block. I removed it and use my EML,still no sound, uh oh. I had it check out by a friend who is an excellent tech. Turns out the recently installed cathode resistor had a bad solder joint. This was corrected and the Elrogs are working fine and sounding fabulous. 
Charles,