After a week of listening to JJ E34Ls, JJ KT-77s, and SED "winged C" EL34s on Dodd amps, I can conclusively say that I preferred the SEDs over the rest. Both JJs were closer sounding to each other than different. The SEDs gave me an airier, bigger (in all directions) soundstage, and a more natural, very pleasant midrange. I may have sacrificed just a little of the slam and transient response using the SEDs, but that is minor compared to the nice sonic gains.
I still need to compare the SEDs to the NOS Mullards.
I still need to compare the SEDs to the NOS Mullards.