Painting fleece or directly painted?

I think Q3 (the definition of it) is rather the minimum for painter's fleece and direct painting.

Are there already any experiences here with puttied, primed, and directly painted? Very prone to dents? Or is it no different from the painter's fleece?

and I thought fleece and (Raufaser) wallpaper would act as sound absorbers and would be installed mainly for that reason? In my apartment I did it that way, but of course I do not know the condition without wallpaper

Q2 and fleece work very well and absorb both unevenness and sound. Of course, you must not use the lightest one, and it must also be possible to glue it, meaning someone who knows what they're doing has to handle it.

We had it plastered (Q2), then worked on it ourselves again with a giraffe sander (one or two afternoons of work), primed and painted. It looks great, but cracks naturally appear here and there over time. I then use a cutter knife to scrape out a V-groove that is wide enough to hold some filler and paint over it. It's still manageable, we don't have a chimney and have lived here for 5 years now. We would definitely do it the same way again.

We had it filled (Q2), reworked ourselves again with a giraffe sander (one, two afternoons of work), primed and painted. It looks great, but cracks naturally come through here and there over time. I then go at it with a cutter knife, scrape out a V-groove that is wide enough to take some filler and paint over it. It still works, we don't have a fireplace and have now lived here for 5 years. We would definitely do it again the same way.

sorry, but how do I imagine a "V-groove"? Do you happen to have a photo (before and after)?

A V-groove looks exactly like a V in cross-section - nothing exciting.