As a valley neighbour I'd be interested in an update when the time comes.
It was mostly okay. It kept working even with the -20c windchill and was always putting out heat.
It's kind of subjective but I feel it struggled a bit eg the 'room' temperature shows a degree or two below the set temp. It never felt cold in the house (but a bit cooler?)
The sensor is probably in the control unit which IS in the hallway over the garage (and that side of the house always seems a bit cooler) so take that info with a grain of salt.