I think this is one of the best ways to integrate smart or dumb smoke/co detectors into ST. I have two that cover the house and they work great. I test them monthly or so and haven’t had any problems. And I have various IFTTT actions to change the LED colors depending on weather, door open/close status, etc.
Edit: I got mine for $30 each, so this is a good deal.
Takes a lot of smoke to get down to receptacle level. My bed sits much higher. I think the smoke we get me before it gets to a smoke detector 16" above the floor.