Linlai E 6sn7 tubes

I purchased a pair of these tubes and look forward to comparing them to the Hytron tubes I have in there now. Linlai seems to get good reviews. I hope that these have good longevity, considering the price, which I don't mind paying if they a quality. Has Linlai been around long enough to get an idea of long term reliability?

@earthbound check here: https://linlaiglobal.com

Clip, reference:

LINLAI™ is a trademark belong to a NEW vacuum tube factory in China – formed by a team of engineers who officially exit Psvane prior to 2019. (This story script is an ‘encore’ of how Psvane was formed a decade ago, when a team of highly experienced engineers exited the state-owned Shuguang tube factory then. In short, Linlai™ team split from Psvane due to irreconcilable disagreement on valuation of investments by both sides.)"

Thank you decooney. 

Phew, I read all 15 pages.  I am interested to hear how this compares to the Shunguang in my DS-2 but am sure these will fit.  My tubes aren’t exposed and would have cut holes due to the socket savers.   Maybe I’ll try the hi-fi version one day since they seem slimmer and look very similar to Shunguang. 
 

I heard Linlai had came up with a new "H" series recently and within it there’re the "CV181-H" & the "6SN7-H". I don’t see them listed on Linlai Global so perhaps it might be just for their domestic market so far? Anyone has a chance to hear the "H" series tubes yet?