I have had a closer look at the Shuguang psvane 845T's. There is a very large image here: http://www.audiokarma.org/forums/showthread.php?s=107c668285cec06d56e3d26723df6ab1&t=318310
Now compare that to the Shuguang 845B. The best image I could find is here: http://www.edsawyer.com/images/845mb.large.jpg (the 845B is on the left).
Note the main difference - the Psvane 845T lacks the solid winged side support, and consequently has a plate at the top to stabilize the tube against the glass. On lesser 845's (e.g. the Shuguang 845), the mica top plate was criticized for causing microphonics.
Starting to have some doubts now.
Now compare that to the Shuguang 845B. The best image I could find is here: http://www.edsawyer.com/images/845mb.large.jpg (the 845B is on the left).
Note the main difference - the Psvane 845T lacks the solid winged side support, and consequently has a plate at the top to stabilize the tube against the glass. On lesser 845's (e.g. the Shuguang 845), the mica top plate was criticized for causing microphonics.
Starting to have some doubts now.