Not that good!
I have 50 Carrier units on my building. Carrier was my choice. Sadly I had no choice in the horrible contractor either. Of the 50 units I still have 8 T-Stats that do not work properly 1 1/2 years since install. The contractor has been zero help getting the issues resolved. The server side of the Carrier platform is horrible. It is not stable. Quite frankly it is junk.