EH 6550s or Svetlana 6550C

I currently use KT88s in SF Power 2, but want to listen to some 6550s. I can easily get my hands on either the Electro Harmonix of Svetlanas so am interested in which of the two people recommend.

The rest of my system is:

SF Power 2 amp
Philly Audio 7B pre
RAW Acoustics HT3 speakers
REL Strata III subwoofer
Shanling T-100 CDP

I listen to almost everything, but lately have been concentrating on acoustical blues and newgrass
EH's will have more high end energy. Ditch thoughts about Svetlana 6550's, they are Sovteks in desguise.

The SED "winged C" (Old Svetlana's) are IMHO far more neutral in tone and very rugged. The only caveat on the SED's is to be sure you get those with rectangular holes in the plates, not the really old ones with round holes, AND, since there have been a few 'hot' ones you take less of a chance of tube run away if you have an amp which uses manual bias as opposed to those with auto bias set ups or limited bias range. I've had one such tube I used in a Primaluna amp which has auto bias and the amp had to be sent in for repairs to the auto bias circuit.
Original Tungsol, Philips ECG, GE 6550a and SED-C are worth pursuing.

Just say 'no' EH and Svetlana (though EH makes a good KT88.)

I'm not familiar with the Tungsol remake.
I put some 6550C-SV in my CAT amps and had great results.
I preferred KT88's in the SF Power 2 over 6550's. The 6550's might have been more neutral, but the SFP2 is inherently quite neutral and benefited IMHO from the hint of warmth of KT88. YMMV.