Would you buy a tube amp if you were unable to use vintage tubes in it ?

I see, complicated subject regarding amp designs and how gentle or not the amps are on tubes. I won't bother the VAC designer with these questions, especially considering that his answers won't change anything for me. I will continue with the best vintage tubes I can find and afford.

Tastes differ, but when something sounds good everyone with hearing will agree that it does indeed sound good. The rest is a matter of preference. You prefer Stradivarius and I prefer Guarneri . 

@wrm57- not a problem. I mistyped your screen name earlier. I did find another cup base GEC U-52, this time a black base, not a brown base. I think it is an earlier production, although someone else who had a lot of these said that the brown base was preferred (my brown base tube still has some life but had some time on it), and the fresh black base sounds fine. Doesn’t surprise me that Kron is not readily available. Are they still in business?

When I retubed everything (all components, not just the Allnic), I did get old stock Holland E810Fs. I had bought some a few years before, never used them, but they were printed on the glass as made in Great Britain. I later learned they were made by Amperex in the States. Apparently, during the golden age of tubes, affiliates took overflow and since both were owned by Philips, no problem. My seller was surprised to learn that- I didn’t return them, they are in one of those boxes of "fresh" old tubes stashed away here.

Even having been in this market for decades as a consumer, there is a lot to learn and nuances that aren’t obvious to the uninitiated- all the more reason to source tubes from a trusted seller. Andy is one of the best I’ve encountered in the States since the Great Disappearance™ of Elusive High End Tubes, but you have to be patient. He can’t always scratch the itch when you need a tube, pronto. 

You have a steady 120 volts and that should be good because gear is made for that voltage.  In some parts of the country, one can see much higher voltage, such as 125-127.  That high a voltage would be of concern for some, but not all tube gear and it makes sense to back that voltage down.  If one can back it down it might make sense to go to the lower end of the acceptable range of voltages such as 110 volts.  My voltage is fairly steady at 117 volts, although it does rise to 120 volts once in a while.  

We get 120 - 124 Volts around here. It’s never been a problem for "modern" tube gear, which would include everything from VAC. It can be a definite concern for vintage tube amps! You’ll see vintage amps with hot running transformers or red-plating tubes for various reasons, but the high wall voltage can be partially to blame, sometimes. 

On my big modern tube amps - no red plating or boiling hot xformers, but the big KT tubes with side-getters do tend to show wear on those side getters, over a year or 2 of use. I’m not sure yet it how much that reflects on lifespan. I've changed power tubes before 2,000 hours unconditionally. But FWIW, the side getters have worn quicker in my VAC tube amps than the Rogue tube amps. It’s a delicate balancing act between power output, sonic perfomance, and longevity. Rogue’s later amps have been VERY conservative on running tubes (a stark turn from their M120 days). But if you do have a VAC, my advice is to not second guess Kevin Hayes’s choices. They’re FINE. 

Larry, I see, so I won't play with step down transformers, I guess, though it could be interesting.

mulveling, Kevin does like certain vintage Mullards and Sylvanias.