Everyone says that SP is safe but i have had a few experiences that say otherwise. I was asleep one night dreaming happily when all of the sudden I couldn't breath in my dream. That scared me and made me wake up only to realize I was on my stomach with my face on my bed. I was unable to breath and when I tried to move so that I could breath I couldn't. After about 20 seconds of terror I broke the paralysis and rolled onto my back, relieved to be able to finally breath. So, my point is SP can be dangerous.