After a long time since SUNO was unfortunately discontinued as a backend, I gave Tunee another chance.
Unfortunately, it failed completely this time as well. Tempo and specifications were ignored, as were layout and structure specifications. My specifications regarding the length of the track were also completely ignored, even though the model gave me feedback that it would generate a track adapted to my required track length.
Unfortunately, the sound quality was still rather poor. Everything sounded very muddy and undefined.
Conclusion: So far, it is absolutely unusable for my type of music. What a shame. 