I've been a smoker for 25 years and it suddenly occurred to me that i'm addicted to nicotine, not to tar, cyanide, ammonia and so on for the 4000 "other" chemicals in cigarette smoke... I'm quite surprised that i have absolutely no craving for a cigarette on day 4 after a full on 20 a day habit, the only 'downside' is the slightly sweet / vanilla tone to the cartridge, but on the whole - the vype e-pen is bloody amazing.