Linlai E 6sn7 tubes

I’ve heard the same thing @lowrider57. If you do a google search for the we 6sn7,you’ll find some for sale. STAY AWAY 

Any opinions on the importance of Grant Fidelity's "top 10% Ultra Low Noise" rated tube designation as opposed to buying directly from China? I need only one tube for my Dehavilland preamp, went to the Linlai website and they were only selling them in pairs. In a Senior Moment I forgot about Grant Fidelity as a possible source and ordered the single tube from a Chinese distributor on Ebay who has an excellent rating. By the time I remembered Grant Fidelity as a possible source (and they do sell them as singles) it was too late to cancel. So, am I forever doomed to neurotically suffer from those incessant ruminations that my tube will not be performing up to its potential, or is this tube grading mostly a marketing ploy?

@weebeesdad , did the Chinese vendor list them as Grant Fidelity "top 10% Ultra Low Noise?" Does the tube have PVT stamped on the glass?

My take after reading the GF website is the Ultra Low Noise is a replacement for their previously offered tube, not just tighter specs on an existing tube. They mention a different tube structure.

@lowrider57 The vendor does not list them as a Grant Fidelity tube. The pictures shown are not detailed enough to show any markings on the glass. It does show a "plaque" on which is engraved "Linlai Tube E-6sn7 - 01512". When I receive the tube I will look for "PVT" stamped on the glass. I was under the impression that GF's low noise designation was just a tighter spec and not a different structure tube, but I could be mistaken.

Thanks for your reply.

@weebeesdad , my first impression was that these tubes were graded higher due to tigher specs, the same way Kevin at Upscale offers his tubes. The choice of tube listed is "Top 10% Cryod" or "QC Pass grade." You may be right, that they're not a new tube. They're a higher grade. 

A rating called QC Pass grade doesn't inspire much confidence in the quality of this tube.