I would not recommend this to anyone. I own an IT company and with the manufacturers support we could not get these devices to work unless I installed a router from 10+ years ago. It constantly fell offline and made it difficult to work with.
The T9 was easy to set up. The 'smart' aspect of it only includes remote control from the app but it doesn't provide any reporting like some other smart thermostats do. I had to turn off Notifications because it was beeping every time the thermostat dropped off WiFi which happened occasionally. Fortunately it would always reconnect by itself. We wanted install this on a junction box but the T9 doesn't come with the adapter that you need for that so we had to improvise. If you're mounting on drywall then it will be fine.
Love, love, love this thermostat. Had a Nest for years and I’m never going back. The additional sensors are great for controlling a larger home and the interface is easy to use. Excellent purchase.