Meth hallucinations (ie, stimulant psychosis) is indistinguishable from reality. It looks and feels 100% real and you are absolutely convinced it's real, regardless of how wacky it is. I have only experienced it once, and it wasn't true psychosis, as (despite what I just said), I was aware I was hallucinating. My experience was that I had been binging on n-ethyl-hexedrone for days, and I started smoking the last of it. I experienced a guy sitting next to me, writing on sheets of paper and occasionally looking at me, and occasionally turning over a new sheet of paper. I could hear his pencil scraping. When I looked right at him, he was gone. I also heard 3 radio stations, which were each coming from a different inanimate object. One of them was coming from my kitchen table, and was a Mexican music radio station. Another was coming from the door, and was a talk radio station where they talked about random stuff and occasionally started describing what I was doing. The third one was coming from the microwave and was playing the most otherworldly glorious music I have ever heard. I walked around the kitchen and the sounds were always coming from the same objects. The guy was always sitting next to my desk. It was so crazy because as far as my senses could tell, it was real, as real as anything else I was perceiving. I think if I had kept vaping the drug, I would have gone over the edge to where I believed it was real, but I was also taking bits of etizolam which is why I think I was able to retain my grip on the fact that it couldn't actually be real.
My friend was psychotic on meth for over a year. He believed with every scrap of his being that he had people living in his walls and hiding in his ceiling, recording his keystrokes. He believed he had $4 million that they were stealing from him. He slashed himself across the face with a knife and believed his brother did it (his brother wasn't even in the same state). He believed he was being forced to make pornos. He believed that the cops were spying on him through the lightbulbs. He ripped up the floor boards and the drywall to try to find the "tunnels" that "they" were hiding in. At one point he smeared shit all over the walls of his apartment and took pictures and posted them all over social media as "proof" that "they" were after him. He insisted that the people were clear as day in the pictures, but they weren't. It scared the absolute shit out of me and everyone who loves him.
It's a completely different sort of hallucination to something like psychedelics. It's not trippy or anything, it's very real, more like delirium.