Great product. Replaced a Google/Nest thermostat. Bought this because of ease of programming and the ability to have more flexibility to set a schedule based on temperature from multiple sensors (rooms). The Nest has pre-defined schedules for remote sensors. The Honeywell T9 give you complete flexibility over sensors and even the ability to set an average temperature across sensors. Very flexible but intuitive to use.
Simple to install, simple to setup. With the configurator on their website, it's easy to determine which type of installation you have. All you have to do is following their instructions. Simple as that.
The thermostat works well and is easy to program. But you need to figure out a lot for yourself because there is no user manual that comes with it. I'm still trying to figure out how the Geofence feature interact with the thermostat's daily programmed temperatures. I assume that when you are out of the Geofence the thermostat default to whatever "Away" temperature you have programmed for that particular day of the week, but I'm not quite sure yet, and I've had the thermostat for a couple of weeks.
It did not work with my Carrier Infinity heat pump. Heat worked fine, but when we had warm weather it and changed to cool, it blew hot air. Tracked to issue with Carrier Infinity heat pump. This was not anywhere in literature or reviews. I am stuck with a thermostat I can't use.