WRL or (decentralized) WRL - yes or no? Advantages and disadvantages?

I also think that a lot depends on the sensitivity of the person

It is above all a matter of interpretation and planning.

Here, only a distinction between central and decentralized is always made. Does anyone have experience with a central extraction system with heat recovery and decentralized wall valves for the supply air? We recently looked at the system at friends' and found it good. Not audible. Hardly even at max. level.

How is one supposed to imagine it sucks cold air into the room without first warming it through a [Kreuzwärmetauscher]? That is nonsense.

If you can't hear anything at the maximum level, in my opinion, something might also be wrong.

I have a Wolf cwl 300, you only hear it at full power. Of course, it depends on many factors, but I am talking about the noise at the valves at a distance of 1-2m in normal operation, which means 80-150 cbm. Naturally, you can also hear 150 at night, but my system is continuously regulated and usually runs at about 70-80 cbm at night, and then you don't hear it.

Central exhaust with supply air valves must be imagined as you described, they are basically simple exhaust systems where the air then flows in without heat recovery through window frame openings or additional supply air holes in the wall, so basically a crutch.

How is it supposed to work that it sucks cold air into the room without warming it first through a heat exchanger? That’s nonsense.

Quote from another forum:

"Exhaust air system with decentralized supply air.
The air initially flows cold into the rooms through the decentralized openings. However, with good systems, you still don’t feel any cold draft because of the rapid mixing with warm room air.
The heat recovery takes place in the exhaust air system.
There is an exhaust air heat pump which extracts energy from the warm exhaust air and transfers it, for example, to the heating buffer, hot water tank, or both."