Air-Water Heat Pump - Experiences

Hello everyone,
we are currently facing the heating question. Just fittingly, on Monday or Tuesday, there was a program where someone paid themselves to death with an air-water heat pump, and it served more as a deterrent example ;(
Personally, I would most like to take a geothermal heating system via probe, but this costs us €7500 more plus the drilling cannot be guaranteed at a fixed price due to the Kaarst rock. So either it works with the first drilling or, if we are unlucky, we will have to pay even more.
Therefore, we are also considering the air heat pump, but unfortunately, you only hear negative things about this type of heating. But are there people who use this system and are satisfied with it and where the costs stay within limits or are where they should be? I know the whole thing depends on location, temperatures, etc., but there are surely experiential values.
I think, first and foremost, you should have a reasonable heating installer who is familiar with the type of heating. I have a meeting on Tuesday with our heating installer who has already installed many air heat pumps.
He already told me in advance about the Stiebel Eltron 16 Trend, which is said to be very good and also eligible for subsidies.

It would be nice to hear your opinions / experiences even if this is the umpteenth thread on this topic.

There are no bad heating systems, only poorly planned heating systems or poor design

Just as a little tidbit: We live in a new development area in the Lower Rhine region. In total, there will be four construction phases with approx. 320 houses (half have already been marketed and are almost fully built). In the first construction phase, the energy provider still offered gas – of 80 houses, (if I remember correctly) only four were connected to the gas network. Almost all the other houses chose heat pumps (there were outliers with pellets or gas tanks in the garden, but you can count them on one hand). Both geothermal and air-to-water heat pumps (all kinds of manufacturers). However, complaints about using the heating systems are very limited, as are the consumption rates in general.

As you correctly write, you have to find a competent heating installer.

There was also an interesting segment the day before yesterday in Plus minus about Kampa houses

That's exactly the one I saw and that's why I started to ponder. On the other hand, I can't imagine that this technology is supposed to be so bad. As [nordanney] also wrote, you probably have to get a skilled heating engineer for the system to work smoothly. Therefore, I just wanted to inquire about satisfied air source heat pump owners. I hope there are some?!

But be careful with the reports, not that they are about air-to-air heat pumps, more people have problems with those, properly designed air-to-water heat pumps are long-proven technology that usually works and is not too expensive.

We are installing a brine-water heat pump and have had more stress with it than I would like so far... now the well driller has no time this month -.- I am now also considering an air-water heat pump. According to the invoice, we have an annual heating demand of 7700 kWh. Assuming another 30% for hot water, we are at 10,000 kWh of required heating energy. Assumed annual performance factor for the brine-water heat pump is 4.7 - let's assume 4.5. Annual performance factor for an air-water heat pump is assumed to be 3. Monthly heating costs are therefore €45 for the brine-water heat pump and €67 for the air-water heat pump. So a delta of €260 per year. The drilling will certainly cost us around €10,000... In year 40 we have the break-even... without interest. Unclear why we still want to drill. So long story short - if an air-water heat pump is properly designed and can operate without an electric heating element, in my opinion there is nothing against it. The milder your location and the better you insulate, the better (air-water heat pumps really struggle when it is -10°C outside).