Apart from remote control (something I can't imagine using more than once to prove it worked), this seems like a less effective solution than programmable thermostatic radiator valves being fitted in each room.
Sure, this can take readings from multiple rooms if you spring for $79 for each extra sensor. And then what. It can do "turn on" or "turn off".
Thermostatic valves on the other hand can control the temperature in each room. On a timer. So if one room heats up faster than another, no need to worry about the wasted heat, the valve will cut the heat to that radiator.
The one thing missing is that these PTRV need to also be wireless, so that they can individually demand heat, no central thermostat at all, just that a room knows it's too cold and demands the boiler comes on. When no room is demanding heat, the boiler goes off.
Combined with the 5/2 24hr programmable timer you can have the bedroom warm slightly at 0700 on weekdays, and at 0900 on weekends, the bathroom the same, living room from 1700 on weekdays until 2100 or whatever is your preference, and each with it's own target temperature.