when I quit smoking in january, (cigarettes) and was only smoking marijuana, I didn't cough in the morning, I didn't cough up crap, I had no sinus problems, and my sense of smell was much better...sadly I've slipped back into smoking them again, and I'm back to coughing in the mornings, and coughing up nasty green and black looking stuff..fuck them, I've done my own personal analysis, and marijuana is not near as bad for your respiratory system as is tobacco..