@eniko So this is the one I got: https://www.aliexpress.com/item/1005005800775381.html
And even though it's definitely a cheap and similar device, I've found that one to be of surprisingly good quality.
I've not had it for long so it's possible that it'll get worse over time, but as I recognize neither the 'bad keys' problem nor the 'bad connection' problem (and the touchpad is fine, albeit small), I suspect this one may be different in some way?
@eniko Oh just realized I forgot to mention this, I got the version with the built-in battery ("Lithium"). Don't know if the AAA battery version has a different build.
@eniko (Some additional context is that I'm picky about keyboards; I get frustrated by most cheap wireless rubberdome keyboards, and use a mechanical keyboard on my desktop. So "the keyboard on this device is fine" is high praise from me, even if it's definitely no high-end keyboard :p)