Some people enjoy it, but the vast majority of trip reports I’ve read are essentially “do not bother to try this, it’s not worth it”. Like DXM, it seems to have different “plateaus”, and the line between a pleasant dose and a multi-day hell of delirious anxiety is rather small.
Very bad. A floormate of mine tried it freshman year in college (of course) and finally emerged from his dorm room two full days later with giant bags under his eyes, and nothing good to say about the experience.