I don't think there's anything special about my unit. As I wrote, people having issues should check their hardware build ID, maybe it's different.

Secondly, it would be great if those having issues said anything about e.g. what software they have installed, especially if they use software from Extras-Devel.

At least two apps from Extras-Devel I tried had serious problems, including (apparently) a huge MEMORY LEAK that was leading to "Operation of the device suspended due to low memory condition". Uninstalling them brought the device back to fully stable state.

Lots of apps in Extras-Devel aren't properly opt-ified, either, and installing them may very quickly use up the WHOLE free space in rootfs. This also leads to performance degradation and other issues.

Software in Extras-Devel isn't of production quality and shouldn't be used by less advanced users. If they do it then it may be the reason of at least some of the issues they experience and blame the device for.