On December 09, 2021, I had an electrician install the new model thermostat - 4iE-V03-WH-01 (to replace the older model 3iE - 6 yr old one that died). It was easy to program, and it works very well. I have no complaints about its operation. My only suggestion is that you offer the 4iE as a landscape (horizontal) model in addition to the portrait model that is currently available. Since the 3iE model was landscape in shape, it would have been nice to simply insert the new 4iE into the same wall opening. Instead, the drywall had to be cut to the new shape, and I now have excess cut out on each side. What were your engineers thinking when they replaced 3iE landscape shape with 4iE portrait? If I were judging your product on that one factor, of course I would only give you a 1 star. But the fact that the product works very well I am giving you a 5 star rating.