The only things I would add as another Tado user (6/7 years now)..
We bought the smart thermostat alone initially. Great as a replacement thermostat. Location based stuff is brill, but working a mile or two away from home meant that the general house temp during the day was only kept a degree or so below the set temp. It’s fine if you manage that by setting a lower daytime temp, but one of the things I liked was that I set temp to 20 degrees and then heating is on or off depending on whether I’m at home or not.
Smart rad thermostats. Nice addition. Bought one for my daughters nursery to control the temp in there somewhat better. Biggest problem, when the smart rad thermostat determines heat is required, the boiler comes on and all rads heat. We’ve since added smart rad thermostats to all upstairs rooms and use the main thermostat for downstairs. So the problem is diminished somewhat.
Also happy to take questions about my experience.