Yeah I can answer this as someone who's very familiar with Chinese brands, and has used several Chuwi devices.
Chuwi is overall a pretty good budget brand. They do more right than wrong. However model to model, there are noteable compromises.
Here, the screen is great for a budget tablet, but the pen is ****e, and the speaker loudness is low.
As I say, it's model by model, because something like the Chuwi Hi10 models had some of the best speakers of any budget Chinese tablet.
And there are Chinese tablets with decent pens. Techtablets is literally the go to, authority on Chinese tablet reviews. Head over there and listen to some of his video reviews, and you'll find something that suits your needs.
If you check his reviews, you'll know exactly where the price compromises are, and where the high quality surprises are, and in general what to expect.
There are strong areas to the Chuwi sur mini, just depends on what your use case is.
The other comment I'll make, that whilst there's no "support", brands like Chuwi have gotten much better at refining the software.
So like on the old models you'd get weird little issues like wifi dropping out, you don't tend do get that kinda stuff anymore.
I've personally owned about three Chinese tablets, never had any issues really. I've used a whole bunch more. There are model, by model weak points, usually the things mentioned here - pen, speakers, wifi. Screens are sometimes ex-Microsoft model screens, and can sometimes be excellent. You get some individual surprises, and where you find those, it's a pretty solid experience.
My current tablet is a teclast x98. I deleted the android partition, originally it was dual boot (I don't advise that process, it's complicated, lol). Wifi is a little weak, but it never bothers me, i'm never that far from a hotspot. Ram is single channel but it still runs alright. Speakers are a little tinny but I always use headphones when watching media anyway.
As I say, Chinese tablets have been getting better. Fully laminated screens are now more common. As are things like machined aluminium backing. CPUs are slowly pushing forward to newer gens. Ram has moved past intensely budget levels. Back in the day, it was a real crapshoot. Now, if you stick with the better brands, check the reviews, you might get some weak points, but you can get some excellent value for money.
I'd recommend buying straight from the OEM themselves though, via aliexpress. You don't need some middle man adding expense, and also tinkering with it, or selling older batches without software patches or early batch issues.