Depending on the model, you'll get different effects, but most prominent is the retro art style coloring, grain, and also texture.
I am using it at weight 0.5. No need for more. Works well with WAI-ILLUSTRIOUS v14, warishita-mix, Duel-ILL-Mix, Hoshino v2. AT least those are the ones I like.
Higher weights widen the space between the eyes, which looks weird, so I don't recommend it.
