I was looking at Glas long before it released to the market. My wife has some health conditions, one of which is only having one lung. We have lately been trying to create a healthier air environment for her at home, therefore, the added air quality monitoring is amazing!Installation of this was a breeze. We went from an old pick your poison heat or cool thermostat where the RC and RH were jumped together to make it work. Thankfully the pull was a 5 wire with a common that was not used (the previous owner of the house actually did something resembling correct!). I took the jumper wire out since this unit controls both over the single wire. Cut power to the entire system so avoid shock to you or the product. Rip out old, put in new and power it all on!The power savings portion is already saying we are saving some money! The house feels like it is the correct temp now where-as the old thermostat felt like it was off. We live in a very old home where there is no return upstairs and the upstairs gets very hot very quickly if you keep the downstairs comfortable. I was able to program the night time temp to be 5-8 degrees cooler which has been amazing so far!Back to the air quality readings. I purchased a stand-alone air quality meter before this unit. I shipped it back within a week because it was complete junk! This, on the other hand, is a quality unit! We can see the ratings in our house and it also pulls the ratings for outside air from the internet so we know if my wife needs to have a day at home vs going out!Cortana is an addition. I'm a Microsoft person by default so I am biased on this front. I also own an Invoke which is in the living room. This thermostat can do 95% of what the invoke does that I have tried so far. Since Cortana is updated on the back end instead of on the device, it should be somewhat future proofed. I read that you are able to add Alexa to the device. I haven't tried yet but may in the future.The online interface is the biggest sore spot of this device. The app is slow... very slow. Hopefully, that is corrected in a future version. I didn't buy this device for remote functionality though so this is a side blip to me that isn't a big deal at all. I know some people live on this feature and it would be a very big deal though.The looks of this thing are gorgeous. We live in a Victorian aged home with lathe and plaster walls. The old thermostat stuck out like a sore thumb. This one looks a little too modern for the house but the clear screen allows you to look past that. I used the white back plate for now since the old thermostat had a huge hole behind it (go previous owner, go!). When I eventually move this thermostat to the center of the house in the living room area, I plan to not use the backplate which should allow a more natural feeling.In conclusion, I love this thing so far. I used bonus points from my card and a gift card on top of the price, that was already the best I could find, to buy this. The normal $320 price is definitely a bit high for this but not by much. I would wait for a sale if you plan on buying it.