Replaced my 17 year old HVAC system that died this year with a heat pump for both heating and cooling last month and am excited to see the savings.

Also replaced our just as old non-working shutters with dual cellular blinds for additional insulation.

One thing I do slightly regret is although Trane / American Standard (they're the same company) is highly rated (according to Consumer Reports) for reliability, if you use a variable speed heat pump and air handler, they use a custom communication protocol (digital instead of analog) that no modern third party thermostats use it, and you have to use Trane thermostats instead.

So far the Trane app works well for manipulating temperature, setting a schedule and holding it like 3rd party hardware and apps, but you're not going to get like HomeKit integration if that's a thing you care about.