One of the best combos so far, the GEC 6V6G with another "holy grail" recti, the French Mazda/Belvu 5U4G:
... and just to see how it would perform in the Atlantic, another French tube combo: the Visseaux 6K6GT with the "compact bottle" 5Y3GB.
Funny that you posted this pic of the 6K6GT as I was just discussing this tube on another thread. Though the original discussion centered on an old quad of Sylvania 6Y6 tubes I had been running we got on the subject of the 6K6 which I have not tried.
As things go the other person mentioned preferring the 6W6 to the others and sent me this amazing picture of one of his Tung Sol lit up during use. I definitely have to find some of these now!