Hey thanks,
well SetToDefaults() is important, because it will override your custom config GamUserSettings in Saved with the ones from Default. So it is indeed a problem.
But thanks for the hint with the Engine.ini.
I was looking through it and havnt found such an entry, but i guess i can just add it.
As you may know you dont have to call save settings as it will be done when you apply your settings.
The intended way is to use the QualityLevels struct inside GameUserSettings. In that struct you can alter the “sg” vars.
After that you call ApplySettings() -> which will execute the cvars and save it to config.