Yes, the Chimera Labs write-up seems to be the 6SN7 gospel. The no. 1 ranked tube, the Tung Sol round plate, is the tube George loaned to David and I, and is the real deal. It's expensive ($450/pair). No 2 on the list is the VT-231 RCA (aka JAN CRC) and I recently bought a pair of those from an Ebay seller for $70/pair shipped. They are warming up in my TP currently. I saw a pair of No.3 (VT-231 Sylvanias, aka JAN-CHS) for about $160/pair. So, the esoteric tubes in this family aren't all ridiculous money, and some other nice ones down the list are $40-50/pair.
A question for you lucky guys with the 6SN7 adaptors. 
In general, how does the transparency with the 6SN7s compare to the transparency using the RCA Cleartops? I am still having a major love affair with the EML/RCA Cleartop combination and am trying to decide if I want to go on another tube rolling expedition. Any thoughts would be appreciated.
Mark
Transparency? Let me see. Hmm....
Ok, I'll first compare transparency on the RCA clear tops vs the Tung Sol round plates 6Sn7's with black glass. The clear tops are a cleanly washed screened window, that if you sit far enough you can't see the screen effect, but it's there. Most of the outdoor details comes through just fine. The round plates are when the screens are taken down to be cleaned and you are looking out of the hole left in the window frame......no screen, no glass pane....I can hear the edges of the soundstage so much better; everything is delineated. OK, so great. Those are $400/pair. How about my recent buy, the VT-231 RCA (JAN CRC) with greyed out glass? $70/pair. Now we're talking...Well, put the glass pane back in, but the glass is Corning optical glass with zero defects. All you get is a slight reflection when the sun is at a certain angle, otherwise no difference from zero glass. The transparency adds to the richness, too. To keep with the same analog, the flowers out the window are much more full of colors and hues and textures without the screen in.
Please note that these silly analogs are courtesy of the EML as recitifer, too, so I have to restate that the combo is the king.....although I heard a few good 6Sn7's with my fat base Mullard, the real transparency, detail and wide bandwidth listening sessions of the past week have been due to the arrival and break-in of the EML and the top-of-the-class 6SN7/VT-231 family of octals.
