It looks like the First Alert combo smoke/CO detector is the only such device approved to work with Ring. Trouble is that it is not readily available in my region.
I understand third party Z-wave sensors can be added to the system albeit with limited capability. Is it worth trying to use another Z-wave sensor from the likes of Fibaro or Abus or would there be very little benefit integrating them in Ring (e.g. if there would even be no notification)?