Who makes the highest quality tube amps?

Electra Fidelity. Hard wired, Huge custom hand wound transformers, Jack Elliano's proprietary circuits. Mine replaced Coincident Frankensteins. No contest. He makes a single ended 45, 300b, and el-34. Also makes push pull amps if you need more power. Give em a try, it might get you off the merry go round.

Bobheinatz, I went the el-34 because it had more bass slam and dynamics then my previous 300b amp while maintaining all the SET magic. I switch between NOS Amperex and Mullard xf-1s which helps. I had their 300b version in my system for a few weeks and it is also outstanding. They share the same class A3 circuit. I don't think you could say one was better than the other, just different flavors due to the tubes. I was worried I would start buying $2000 Takatsuki tubes and coming from 300b wanted to try something different. I have also had the pleasure to hear the 45 in Jack's
home system. Quite an awesome little amp just not enough power (1.5 watts) for my speakers. Let me add that Jack and his partner Tony are an absolute joy to deal with. Jack is so humble, without perusing an old online interview I would not have known he worked on the NASA Gemini project,
was a recording studio engineer, holds multiple amp circuit patents, and hand winds the finest transformers. It is guys like Jack, Ralph of Atmasphere etc. that make this crazy hobby great.