This new old stock-testing, perfectly-matched pair of Ken-Rad 6SJ7s was tested on our Paul Hart-calibrated TV7/U for shorts, gas and transconductance. There were no shorts or gas.
Transconductance measured 58 for Tube One and 58 for Tube Two where minimum (65%) is 40.
They have E5E and E5E date codes, respectively.
I am playing them as I write in my Musical Paradise MP-301 MK3 and they sound excellent. They are microphonic and are fine in the preamp stage of my MP-301 and other gentle environments. They are, however, totally unsuited for use in guitar amps or any other vibratory environment.