I've heard of CXMT RAM and it appears to be solid in the few tests that exist, but by 'viable' I meant commercially viable. Even with current RAM prices (where their stuff is barely any cheaper than reputable brands), I don't know how much they rely on subsidies from the Chinese state. Production capacity appears to be limited, with one issue being relatively low yields, just 80% for DDR5. They are also using an outdated 17 nm process, which means it's running a few degrees hotter than the competition (and you need more or bulkier chips for the same capacity) - make sure your system airflow is up to snuff. This is what I meant by playing catch up with moving targets.

Granted, you don't need the latest node for every computer, especially in the consumer space, but personally, I wouldn't risk running RAM from an unproven vendor (same with storage). I've had issues with faulty RAM in the past, which, among other things, resulted in data being invisibly corrupted over the course of months, so I tend to err on the side of caution. If their stuff turns out fine over the course of the next four or five years or so, I might probably change my tune - or be simply forced to buy from them, if for example the memory shortage continues.