love the system
at the risk of reader disgust/pity/abuse I have to confess I love my Nested up house. My partner is rather into candles and incense and the like and I'm a passionate kitchen abuser and pre-nest (smoke alarms), we ended up taking the alarms off because of so many false alarms. Which on two occasions means rather more damage caused by candles gone wrong than we'd ideally have liked.. (a touch of understatement there)..
the nests can be hushed - before they go off - (yes yes, that wavey hand thing was daft) with a swift push of a button on the alarm itself. So they're now always up and running.. success!!
as to the thermostat - it does know how long my house takes to warm up and cool down (at 4C ambient, it takes 30 mins for 0.5C across the house with the vent system open)