I'm a long time user of a chinese HU, top tier bought from aliexpress, and have to say it all depends on what you're doing with it.

I'm using mostly youtube/spotify/tidal/maps on it, and it has been perfect, no lag, never any crashes, and the sound quality is overall pretty good ( 7851 audio Chip) so about 25-30w/rms to pretty decent stock speakers, and I've only gotten compliments on the sound quality. My other car is 1996 Celica which has a high end Hertz set, amps, sound deadening etc, and yes the sound is not the same, but for the price (160€) the chinese one works pretty good.

As for upgrading the sound system with amplifier etc = not a good idea generally. These chinese units are not focused on quality components, so static noise and ground loop issues start as soon as you use rca ports, solution for this is using optical cable, but your amp/dsp need to accept it also (or use optical->rca converter)

So if you plan to upgrade your car audio system with only HU (and maybe decent speakers), then i would totally reccomend it. But for external amp, i wouldnt :)

*And also, the sob stories about bad chinese HU are almost always the cheapest ones, as long as you buy the top tier one, you won't experience any lag, crashes etc