I suggest adding EML 300B mesh plates to your list. To me in my system they are considerably better than other new issued 300Bs I tried. While I have only tried a few 300Bs I have gone through many 45s and 2A3s including a few rare globe 45s. The EML mesh plates are in all my 45s, 2A3s and 300B amps now. To me they have been consistently the most transparent and balanced tubes.
Elrog 300b vs we300b
I am looking for an upgrade to my elekit tu8600s. Currently have cossor black plates. I use the amp for my hd800s and zmf atticus. I am looking for more transparency, dynamics and a bigger stage. I am interested in a richer tone too so not sure which direction to go. Any thoughts?