Excellent upgrade investment
Line thermostats super easy to install. In ’80’s and older homes some creative wiring and replacement of external transformer relays is needed for 3rd wire in relay thermostat. All thermostats work very well. I like the displays especially the one showing the percentage of the max heat being provided by the heating unit. You might add that 2 (or more?) relays can be run by one thermostat. Great to have rooms warm when you arrive.