I have a 3080Ti and it took 46 hours. Way too long, I would rather just upconvert. I only do 720p to 1080p.
Chameleon
Another thought about the 3080 Ti. UniFab includes RTX 3080 in its supported NVIDIA graphics cards, but doesn't list 3080 Ti. For some others, they have included Ti. Don't know how much that difference matters. However, we know some cards/GPUs don't really help. I have no idea what does. I don't know how to find out except to ask around.
Oh yeah, and before I forget, I tried setting UniFab AI to video only instead of auto (video + audio as much as UniFab decides it can enhance) and it didn't seem to speed up enhancement. Video is obviously MUCH bigger and more demanding than audio.