Summary: A heat pump air conditioning system heats your home in the winter and cools it in the summer. Heat pumps are very energy efficient and usually pay for themselves quickly.
I started using heat pumps, or more specifically, air to air heat pumps decades ago. I found them to be energy efficient, easier to install than separate heating and air conditioning systems, and extremely energy efficient.
Over the years, air to air heat pumps have gotten even more energy efficient, quieter, and most importantly, able to heat homes without calling for their gas or electric backup system when the outside temperature drops well below freezing.
Compressor technology has made great strides allowing heat pumps to draw heat out of sub-freezing outside air.
I would not build a new home or replace an old heating system with anything but a heat pump, unless I lived in an extremely frigid climate.
The only real complaint I ever received from a home buyer was that the output air from the heat registers, which is called the supply air, seemed cold, or colder than normal.
I explained that indeed the air is cooler than output air from a gas furnace by several degrees, but that this keeps the system from cycling too often. Less cycling of any heating system results in more even or steady room temperatures. It also results in using less energy.
Carl Heldmann