First Alert SC5 Hardwire Smart Smoke & CO Alarm vs First Alert SMCO410 Smoke Detector & CO Alarm

These two First Alert combo alarms are nearly identical on paper, so the First Alert SMCO410 Smoke Detector & CO Alarm edges ahead here mainly on its lower price, while the First Alert SC5 Hardwire Smart Smoke & CO Alarm holds a rating advantage. Both detect smoke and carbon monoxide with a built-in siren, steam-check tuning, and the same 10-year manufacturer warranty, but they get there differently: the SC5 Hardwire is mains-powered with a battery backup and links into Google Home over WiFi, while the SMCO410 runs entirely on a sealed lithium battery and connects over Z-Wave, aimed at Home Assistant and Ring Alarm setups rather than Google's ecosystem. That installation and connectivity split matters more than the tied spec sheet suggests: pick the SC5 Hardwire if you have alarm wiring in place and want Google Home alerts, and pick the SMCO410 if you want a battery-only unit that plugs into a Z-Wave or Ring-based smart home instead. For most buyers without a strong platform preference, the modest price gap tips it toward the First Alert SMCO410 Smoke Detector & CO Alarm.