A family member recommended the T9ST. Great quality, value and performance. A little learning curve on installation (if additional wires need to be connected). The large digital display is easy to see and you can control thermostat with your phone. (need to download app). It's nice to have a smart thermostat.
This is a great upgrade to a standard smart or standard thermostat. The room sensor allows us to have an average temp on our upper and lower levels. We also have the ability to specify an active room and of course control everything remotely using the app. Installation was a bit long, but that was because we had to rewire some of the default wires on our furnace. Overall, not too difficult for a DIY'er.
Menu is not intuitive. No Windows version of app If you have used TCC before the switch over to this app is confusing Why are Home and TCC incompatible with each other?
I upgraded from a T-5 to a T-9. There were good and bad points to the installation.
The mounting bracket for the T-5 was behind the wiring harness, and unlike the wiring harness, the mounting is not interchangeable With the T-9. So it all had to come out. However, since the wiring harness was the same for the T-5 & T-9, I didn’t have to figure it out again, I simply took a picture of the original wiring and copied it over. The T-9 works as promised, allowing me to give priority to my upstairs master BR when my wife and I are alone, but can switch to the hallway between all upstairs bedrooms when we have guests. It should be sold with 2 remote sensors since that’s its number one selling point. The T-9 also works seamlessly on the Honeywell Home app alongside my remaining downstairs T-5. I wish that these thermostats would “talk” to each other and share vacation modes when desired. But overall, I’m pretty happy with my upgrade.
Very easy to install, with very good instructions including hooking up a Common wire.
I really like the simple and unobtrusive design, with settings to automatically dim the display when you want. While it takes a bit of practice to get used to the menu system, it's also easy enough. Having a remote sensor is great in an old house with poor HVAC design.
Bottom Line: A high quality product that I'd really recommend over the pricier and more complex competition.
This has made a huge difference for us in being able to manage our electricity and remotely set it up. Some very cool features come with this thing like geo-fencing. All in all, my only real complaint is that the additional room sensors add up quick. I would expect them to be about half the price they are.