Modern EL34s VS NOS Winged C - and return policies?

@pdreher 

new stock tubes, particularly Tung Sol KT150's take a long time to settle in... at least that has been my experience

I can't disagree with you. My only experience with Tung Sol KT150's was in an overpriced, crappy, US made integrated. It was red. Not that I'm naming names:)

The best they sounded was they day I boxed them up to trade it in.  

Conversely, the best power tubes I've owned were NOS Shuguang 6L6GC "coke bottle" (circa 1970's I believe). They did sound great as soon as they warmed up.

All fun stuff but I've simplified things with a SS amp and tube sources; DAC and phono stage that both use 12AX7's.

@whiteknee IMO original Tesla EL34s are a great sounding tube. I have two small amps that can run EL34s.  My Inspire KT-88 can also run 6L6, 6550, KT-66, 77, 88, 120, etc. I have pairs of St Pete SED S, Winged C EL34s, Tesla, RFT, GE and Sovtek 6CA7s (American EL34 equivalent).  The Teslas have that warm, rich, midrange, are balanced, with a touch of treble roll off, and good bass response. IMO, second only to the St Pete Svets.  The Svets have a little more treble extension and perhaps bigger soundstage, although in a blind A/B probably difficult to distinguish the two. 

RFTs brighter, edgier, with less warmth in the midrange. 6CA7s are more balanced than all of the above, almost clinical transparency without richness, like a studio monitor!  GL KT-77 are also super balanced but with a touch more musicality. NOS Svets and Tesla rule in my two rigs.

The best El34 current issue tubes I've tried or hear are the PSVane EL-34 PH (Phillips reissue). A great Chinese source for 4 matched tubes $292 is https://www.jjyaudio.com/productview.asp?sid=9030 Helen is great to deal with.

US based dealers will charge about $450 to $500 for a matched quad

@trivema Thanks for your insight.