Regarding Chinese tube amps. from a maker in Hong Kong, I bought a tube pre amp which started out selling on line for 1 grand. I got it for$400. There is no support for this maker in the USA. When it brought down, early on, I mailed off for the schematics, waited a month. Got them, weren't much help.Ended up with an older Van Alstine tube pre-amp. While there a some who have the cash for big purchases from China, I would urge you to consider the work of Frank Van Alstine. You won't be disappointged.