Peyote is wonderfull. But i do find it to be pretty inconsistent, like all of the other cacti. I've had peyotes that felt almost like pure mescaline, but i've also had peyotes that had a lot of other stuff in it.
I think the problem with peyote, is pellotine. Pellotine is a sedative, and maybe a bit of a deliriant. The mescaline/pellotine ratio is not fixed in these cacti. If you have a lot of pellotine in your peyote, then the experience will simply be far less clear, and more disoriented as well.
Putting your cactus in a dark place, and not watering it for a long time, will increase the mescaline content, but not the pellotine content, i think. Because my best experiences where with cacti that i didn't water for at least a couple of months.