How long did you own your amps before you changed the tubes? How long have you owned your guitars before you changed your pickups? How long have you had your car before you changed your tires?
Longer than day 1 I suppose. That's because they work just right for the item. Will you change your tire after buying your car brand new? Do you see ferraris with ordinary tires?
The hot box is supposed to offer a signature sound. You can't offer that if you're expecting your consumers to change a part right away. They can and will probably change the tubes, but normally, after they have used the item extensively and just want's to experiment.
When you're offering a boutique item, you're not offering it for cheap. They're boutique! It is expected of them to be expensive.
Whups, mis-posted. Let me try again.
When I was a newbie a very long time ago
the tubes that came with the amps I bought stayed in for a good long while before they were changed. In the last 15 years, however, I can't think of a stock amp I've bought that didn't get an immediate tube change within 2 hours of my buying the thing. Just as an example: There was a Matchless Brave (40w, 1x12, 2-EL34's, 3-12ax7's, 1-5ar4) that apparently sat in a store called Soundsgood Music in Greenhills for many years. The darn thing cost so much and sounded just average to some people, that no one would touch it with a 10-foot pole. When I came upon it, inspected it, and tested it in-store, I talked the folks down to a decent price level and they were only too happy to have someone take it off their hands.... finally.
The second I got home, out went the Chinese Ruby Tubes 5ar4, the Mesa-branded Russian EL 34's, and the russian 12ax7's -- in went all NOS Mullards in every tube socket. I gigged that amp moderately for about 5 years, and finally changed out the Mullard EL34's for a pair of Siemens earlier this year. The Mullard rectifier and 12ax7's (except for one that died about a month ago) are still the same ones from almost 6 years ago. Have been very happy with it all the way. Still gigging the amp 1 or 2 times a week at stage levels these days. No problems at all.
Following the same logic, a lot of people pass up the usual panasonic or "ibanez" branded alkaline batteries that came with their new expensive TS808 re-issue tubescreamers in favor of Energizers or Duracells.
They don't even sell highend Tennis rackets pre-strung. You have to choose your preferred string and specify the tension.
Re: Ferraris, the factory will stick in good production tires from whatever tire company they are able to swing a supply deal with for a good price. They will be excellent tires that are several notches up from the run-of-the-mill models other makers put on their cars, but they will not necessarily be the most technically advanced, best built tire ever available on the market in absolute terms -- the kind made up of special stuff used by formula 1 cars for the Indy 500 -- specially formulated, constructed, selected, inspected, tested, and , etc. where money, glory and fame are on the line. Doing that will make the car's sticker price absolutely outrageous. And so many new anal Ferrari (Porsche, Maserati, Fill in Hot-car-name-here) owners opt to upgrade their tires too with whatever Pirelli, Michelin, Fill-in-other-high-end-tiremakers-names-here makes that outspecs the original tire. They may do this at a later date because it isn't as simple a swap as what one can do in the comfort of your living room.
The point is, the original tubes have their own character which some folks think is ok. No problem for them. The tubes do work and there's technically nothing wrong with them. Interesting thing with some of these amps/pedals is that although there is the promise of a signature response, it will actually be very different with any combination of guitars, amps, and other gear in the signal chain. So there really isn't one "correct" result. The best results for you is actually an outgrowth of choices you make in the consumables and other stuff you attach to it. At the end of the day, no sense in making such a subjective choice for you when it would likely add another $100 to the pedal's selling price. With something like this, it just makes sense to go generic.