ditto.Mine is running well as follows with a 3080 TI.
Graphics Options:
Everything set to High, including RT. RT enabled on all 3 options.
*Some of these could go down to Medium or Low such as fog quality or sky quality.
Display Options:
DLSS: Quality
Sharpness: As you like
Reflex: I don't really notice much difference with this, except adding it tends to use more power when enabled in combination with High or Quality presets.
Framerate: Cap it in RTSS or here as appropriate. I typically target 60 FPS but if I get excess power via solar or cheap Go rates, I can set 120 instead and use the extra frames.
Other things I've done:
Updated DLSS version to latest.
Engine.ini setting changes a few posts up from here. My r.Streaming.PoolSize value is half my VRAM currently, 3080 TI has 12GB so (12 / 2) * 1024 = 6144.
Set Shader Cache to 10GB in NVCP.
Think that about covers it.
Quite surprised how well the game responds, not noticed any slow downs (even in places where other said there were slowdowns - sorting hat and Hogwarts).