Anyone have experience with the Tung Sol 7581a vs. EL34, KT66, KT88, 6L6


I broke down and added another power tube (Tung Sol 7581a) to my collection.  That can get expensive as my Primaluna Dialogue HP Premium integrated has 8 power tubes.   

Why has this tube escaped me thus far?  Why is it not more popular?   Many folks don't sell this reissue tube.  

I think this is a great deal.  I was torn between the lush, thick midrange of the EL34 and the more evenly spread out sound of the KT88.  But the KT88, for all its more correct behavior didn't romance me like an EL34.  

The 7581a from Tung Sol can be had cheap and I really like them.  [I'll spare you all the audiophile terms].  They check the boxes that I was looking for. 

Does anyone have experience, information or knowledge about this splendid tube?  

PS  The next experiment is KT150s but I can't see doing it if I'm gonna lose any of that great EL34 midrange. 
128x128jbhiller
JB you might want to add a Winged C EL34 to your list. I have never heard of the 7581. Is it a hybrid of EL34 and KT series maybe? 
I bought a pair of new JJ KT77s and they didn't sound as full and clear as the supplied Gold Lion KT88s or the Sovtek KT88s currently in use in my Dennis Had "Fire Bottle" SEP amp.. Are the Gold Lion KT77s simply better tubes? If so, I'd be willing to check em out…I tried the JJs with various rectifiers to see if there was some synergy issue, but went back to the 88s. Still, curious.
@wolf_garcia I can't comment on JJ KT-77s but in my system the Gold Lion KT-77s crushed JJ 6ca7 fat bottles, Psvane Phillips replica EL34's, Svetlana, EH EL34's as well as Tung-Sol reproduction EL34's. I can say they are great tubes and worth trying out.
jbhiller - Where did you buy your  Tung Sol tubes?  I've got a PrimaLuna integrated (older model with 4 output tubes) and might just try the Tung Sols.  I've tried the stock EL-34's and some Russian KT120's - but currently I'm running Gold Lion KT88's which, so far, are my favorites.