Just hooked one of these up, not bad! Anyone know of a way to integrate it?
nope, it’s a proprietary system 
It’s a nice device.
The previous generation was proprietary and couldn’t integrate with anything else.
This new model is HomeKit enabled and can therefore integrate with anything that supports HomeKit. However, the current generation of SmartThings does not support HomeKit. So there’s no direct integration.
In the United States, all smoke alarms and CO2 alarms have a specific audible pattern. For that reason there are audio monitors, for example the Leeo and the kidde remotelync, which are able to listen for a smoke alarm going off and then send a text or wifi message. Because these are triggered solely by the code-required audible alert, it doesn’t matter what brand the smoke detector is.
You can then have that message go to IFTTT, and get indirect integration with SmartThings that way. The question as always with IFTTT is how much lag will there be.
I’d second getting this alarm ntegrated… As mentioned already, the proprietary protocol is a hurdle.
I contacted First Alert to find out if they were going to support anything other than HomeKit/iOS and their support rep made it sound like it’s a definite possibility but nothing is set yet. Hopefully SmartThings steps in and works with them to get official support.