Hi, I bought the Ecobee 3 a while ago and I am really happy with it. It has the ability to create multiple zones and or sensors that you can use to reroute energy to the rooms that are most important to you. I really like this as I work a lot from my home study room and spend a lot of time there, so I can set up the thermostat so that most of the warmth goes to that room and other rooms that I do not use do not get heated, thus saving me money. The ecobee multiple zones option is really neat. However, you can also opt for the Ecobee 4 but it is a bit more expensive since it is newer.