Spice and other herbal blends are honestly not worth it. The high is short lived often leading users to binges. Newer herbal blends are less potent and tolerance builds up fast leading to psychical and psychological addiction. I've only smoked these blends a few times mostly because of peer pressure; I've never bought a vial for myself. These blends can cause death,brain damage, and damage to the CB1 and CB2 receptors on the brain, these receptors are responsible for producing the "high" marijuana gives. However these synthetic chemicals primarily work on the CB2 receptors