I own a Yaqin MC-10T. It's a PP EL34 amp. Sound, though not as good as my EICO HF-60s, is still quite impressive for the low price. It has a very 'modern' / fast sound. I ran mine for many hours without any issue - currently on loan to a friend who put it through its paces.
Modding them is a bit of pain, though I did manage to replace the stock blue coupling caps with Wimas.
I preferred the sound of the MC-10T over many vintage tube amps I've owned, including the Dynaco ST-70, Mark IIIs, Mark IVs, various 6BQ5 amps, and a H-K Citation V.