Worth watching in the background or skimming. Seriously y'all, test. Not only do you keep yourself from ingesting random stuff, but you help create a market for unadulterated substance. Many, many deaths reported as "overdose" are actually a result of people taking drugs they had no idea they were taking (25I-NBOMe is a good example).
Bonus reads:
http://www.newsweek.com/bath-salts-found-40-percent-ecstasy-users-428343