[jltsiren]

That depends on climate. The longer and colder your winters are, the more you benefit from the reliable efficiency of a ground source. Ground source heat pumps have been the most common choice for heating new single-family homes in Finland for the last ~20 years.

[giantg2]

Installation is probably relatively cheaper there due to volume too. In areas where it is less common, there is less competition and fewer options for competent installers.

[soco]

True but even then there are other criteria too: as I plan to sell the house in 10 years, the extra cost for drilling simply didn't make economical sense (to me). So the "regular" pump had to do, and does it fine.

[dzhiurgis]

There is barely any people living in those latitudes. In Lithuania last 10 years air to water pumps completely took over.

Now you also need consent to drill making it much too difficult.