Nobody knows for sure. There are purportedly two, perhaps three active elements in the mushroom. It hasn't been studied enough for us to know if there are more. If indeed that's all there are then it stands to reason that any differences in the high between one expression of the gene and another is all in your head. If there are more than those three then there might be a difference one from another. I and many I have spoken to swear they are different and consistently so. Others claim no difference. I wonder if anyone has tried a double blind study. Have, say, four different varieties, have three or four people eat measured doses of one, record their experiences and do it again in two weeks until all have been tried. I suppose there might be some sort of dose dependencies as well that might need to be adjusted for. In other words, it is possible that a two gram dose is not enough to have the user derect a difference between one and another but they might notice it in four grams.