Some great discussion here @rooze @larryi and @tsushima1 I have also heard that Synthesis A40 actually driving the exact same speakers I own AN-J/lx's really lovely sounding and such a good value. I've not ever owned a 6l6 amp but have always been curious so many folks I know with good ears love them, I also love the KT77 tube as a replacement for the EL34.
That Sansui amp looks great and I'm sure it sounds fantastic I'm guessing if you could find one it would be serious $$$. And yes iron is king I've been lucky to have bback to back amps using vintage trannies first Accrosound and now Eico and love that sound.