Good morning! Yes indeed, the house is standing, we have moved in, and we built with the 36 cm PP2 Y-Tong, some load-bearing interior walls are PP04. Overall, I have to admit that when noise comes into the house, the windows are the weak point. Rely on SSK IV, that helps extremely (we have that in the living room, bedroom, children's room). I would save myself the PP04 in your place, as it also has worse insulation values. What does your environment look like? What are you currently planning? Next to us is a village main street with cobblestones - a 30 km/h one-way zone. Traffic is very manageable, zero at night. You hear nothing from the asphalted road.
I also did the test holding my ear directly to the cobblestone street against the wall (house is about 5 m away). If you concentrate, you can definitely hear it; it also depends on the vehicle. But if you sit 1 m away, it is not noticeable. So that's more something to get worked up about.
We are satisfied with the stone so far, also regarding thermal insulation performance. Our humidity values were also very good after a short time. Alternatively, the T9 from Poroton is pretty cool. If I were to build again, I might choose a sand-lime brick with mineral insulation and clinker. In the end, that is significantly more expensive, and believe me: you don’t think about it anymore when everything is finished.
It’s definitely not as bad as some sometimes make the 36 cm PP02 out to be. And the dB value is not terrible. Of course, the sand-lime brick is better in that regard. But in terms of economic efficiency, aerated concrete is probably hard to beat.