Bests & Worsts Reviews from Amazon

First off I had a 4-wire thermostat that was on my system with 3 postion switch... heat off cool.. No emergency heat...it's a air conditioner with an electric heater (not heat pump heater) all in one Goodman unit ..... there was a yellow wire. a green wire ..... white wire and a red wire....and a jumper wire between RC and Rh that's all... I had no C wire and this absolutely 100% works on my system with no C wire the batteries keep the screen lit ....... the wifi everything hooks up fine..... So 5 stars for the thermostat pretty easy to setup.. Need to start a account with sensi Free no big deal.. App works great.. Now for me the downside is it doesn't work well with Alexa it doesn't do the basic commands you can go to heat and you can go up and down on the temperature. Couldn't get it to actually turn the AC on or turn the unit off..... The Sensi app works fine up down temperature everything works great heat ac automatic... just doesn't work all that that smooth with Alexa. Over all .... So if just a good easy wifi thermostat I would highly recommend this....... Updated update update update 1/28/18 wife figured it out... works great 10 stars You have to say exactly Alexa set thermostat setting to cool Alexa set thermostat setting to heat Alexa set thermostat setting to off Alexa set to what ever degree you want