winged c 6550c is not good for ref 5se??

I ordered 3 of svetlanan SED winged C 6550c from 'Upscale audio' last week and it was not shipped until today, so i call them to find out what is going on here.
They told me they didnt send it because " This tube is not going to work well with your audio research amp and it will failed almost every time".
Is it right?
You're welcome Misternice. Something I did find is when I owned Dynaudio C1 and C1 Sig's the TS 6550 black plate sounded fantastic. The *EAT KT88 and TS KT120 sounded horrible. But when I upgraded to Raidho the TS are too warm sounding and the KT150's are better but far from my favorite. Right now with the Raidho's D1 or D2 the Ei KT90 is my favorite. May need to try the EAT KT88 again.

* With my amp the Octave V70SE and now the V110 I have had horrible luck with the EAT tubes. I've been told the EAT was designed with a 450V plate voltage (although rated at 600V) and the Octave is 540V for the V70SE and low power for the V110. Out of a quad and pair I lost 3 within 60 hrs. Out of a quad of KR Audio KT88 (really EAT) I lost 1 in less than 20 hrs and still have 6 left. But that said I did buy the tubes used from a great reliable seller. The EAT KT88's were the most linear/detailed/clearest sounding tube for the short time I could listen to them.
The issue isn't with the Preamp, it's with the Winged C 6550. Don't use them! The last of those tubes that came from the factory before the plant burned down were awful tubes. Use a 6550WE. That is what ARC is using now.
Yes,I know what youre saying,different combinations.I have a different flavoured pc and sc,to play with,to fine tune things.The GE works best for me now.I would like to get the record player going next year,that may change things again.One tube,cheap upgrade really.I haven't explored the kt tube yet,maybe next year.
I bought Winged C from Ebay from Earyly 2000 Production. Hope they will work fine.