I bought a pair and they work great on our two zone home. The only surprises were having to install a different app from our previous Honeywell WiFi thermostats, and the default settings for the backlight was too bright. Once I figured out how to turn them off everything was fine.
Thermostat is very simple to use and overall a great product. However, there have been multiple times the thermostat has decided to disobey the set schedule with no user interaction. It is also difficult to view the secondary sensors on the app. I hope they make this easier to use in the future.
Took some time to figure out best settings for 3 level townhouse (cold basement, hot master) I resolved by putting sensor in basement and 3rd floor master, master as primary (82 day/75 night) - sounds warm but makes the basement comfortable and the main floor perfect. I love this system, gave 4 stars because I keep having to reset for outside temp and it keeps defaulting primary back to Kitchen, where the Thermostate is; still trying to figure out why.