Didn’t PSVANE buy out the TJ FullMusic stuff when that company discontinued? I forget if it was large power tubes or all tubes. It would be of interest - where that could go.
Seems PSVANE has less competition in China than before the pandemic, and now with Russia also largely off production... I don’t suspect these things will depress PSVANE prices, and for technology that is physically and environmentally challenging to make, higher costs should be expected today - not the opposite ( @knotscott 😉 ). These devices are kinda like camera film nowadays - fun as they may be, they are super niche!
Anecdotally, I’ve had a good time with PSVANE and FullMusic preamp tubes.