A lot of you have nice amps that essentially require quality NOS tubes.
- NOS tubes are not a necessity --they are desirable.
- Do NOS tubes sound better? -- that depends on the tube and the source from which they came.
- Are you into tube rolling? -- that can get expensive.
There are plenty of good, newer production tubes available, e.g JJ/Tesla in Czechoslovakia,
Svetlana in Russia, Shuguang, China.
I don't see production shortages any time soon.
I have an EL84 based integrated amp (2 EL84's per channel), 3 ECC83's, 1 ECC82 and 1 6DJ8 -- that's 9 tubes total.
None of them are NOS tubes.