Your comments are spot on. I wonder, how the sound of both tubes will change with break in. Maybe they will sound closer to each other. Anyway, I am now listening to 242, and I have no desire to go back to 300B
I've sent my 300B back for replacement.
I still like that RK, though. It does things nothing else does. The word "architectural" springs to mind, for some reason. Compared to most, it is a bit flat in the z-plane imagery wise. But it seems to hold a soundstage of great structure and assumed ease - it has an air of confidence about it. It's like "this is quite an easy job to do, isn't it". I caught it sounding a little dry yesterday on some material. But I still like it.
Another goodie is the EML Lampizator 45 6th Anniversary Special Edition (mesh plate). Way better than the EML 45 solid plates I had for a while some time ago. I thinks it's is fabulous - really sweet, spacious mid range. Just lovely. They should make some more.