I have one of these and as far as I can tell it works.
One complaint I have was that there was one tube of the pair that while warming up sent out a big blast of noise, I discovered this after I blew up one PC28 Output card in my Dynaco ST416 Amp, caught on fire about 2 seconds after I turned the MS-22B on. I was later able to 'hear' this 'noise' using a pair of old headphones instead of an amp. The vendor supplied me with a new pair of tubes and now it works as expected. I am new to tubes having spent the last 40 years in Solid State only so how to verify the tubes are OK is still a mystery to me, so I depend on the manufacturer (Yaqin) to verify all parts before shipping.
Now it is connected between my SYSTEMDEK II turntable and my Yaqin MC-100B integrated amp and everything sounds fantastic! From my observation of these two components in action I can say that I find this a very very good way to listen to records!
I am still using the stock tubes and I am totally pleased with the sound this set of components provides. Maybe after 10,000 hours of use (or component death) I will update the tubes, but for now I am happy with the Chinese tubes.
I did my 100 hours of burn in on my bench, then I replaced my old Dynaco ST400 and Pat-5 preamp with the MS-22B and MC-100B.
If I were going to do this again the only thing I might change would be the color, I bought the Black & Silver, next one will be the Gold & Green!