i am sorry you had that bad experience with the ultrasonic cleaner... but just so i am clear, you bought those cleaners, and had the negative experiences ( folks with bad english and all) with apos? sorry if i missed it if you posted this clearly earlier ...
my point about the ’broad brush’ is that if your experiences were in fact not with apos, and you are assigning these negative traits and factors to apos and this thread (given the op’s beef with apos) just because they sell chi-fi gear... doesn't seem fair to me
not that i am invested in any way in protecting apos - i just bought a topping mqa dac from them last year, tried it, then returned it, and that is all i ever had to do with them.... but the person i dealt with to handle the return authorization was an american dude, and return shipping was to oakland ca... so i think, in this particular case at least, the folks at apos and the chi fi brands that sell through them to usa customers are in fact trying to improve on the kind of situations you allude to - to be sure, there are pitfalls to buying straight from a china vendor in say, shenzhen, then the awkwardness of returning it or needing support when the product arrives
another separate, interesting, positive example is alvin chee at vinshine, based in singapore of all places, selling denafrips dacs, and supporting customers in the usa excellently (see the other live thread on denafrips, with plenty of happy, appreciative customers) - his responsiveness as a retailer is well documented by many and the product is good - alvin has also set up two usa service centers in the usa to support that brand...