Hey it's my first post!
Back in 2011 my friends and I were regularly eating 400mg hydrochloride salt derived from peruvian torch. It was always what we considered a sufficient dose, but being naturally curious we started taking larger doses. The highest I personally ever went was 1500mg. It seemed that the insightfulness of the trip went right out the window, and a character of disorientation or dissociation began to take hold. It was certainly fun and challenging, and it was indeed hard to imagine during the trip that normality was anywhere nearby, but the next day I only felt mildly more tired than the usual day-after-mescaline feeling.
A few years later I titrated doses from a different batch of cactus and found that 250mg bore more similarity to the 400mg trips of yesteryear, and when I tried 400mg it completely floored me and was nearly overwhelming with very loud musical/auditory hallucinations and a strong unpleasant vibration throughout my body. Taking 1500mg of this seems like it would be nightmarish.
As for visuals, I've always felt like mescaline has a lot in common with LSD in the visual arena, which is to say there is barely any effect there. Some noise, some changes for example in the perceived size of the visual field, and the occasional change in the perceived shape of the visual field (sometimes with either drug I feel like I am looking through a television set, that the corners are distinct corners, not rounded off like normal day-to-day vision). But as for visual hallucinations, even taking 1500mg had a much stronger effect on the patterns of thinking and openness of emotion rather than on perception. Mushrooms and DMT are the winners of that particular competition.