I went cold turkey around 3-4 months ago and still going strong, I did slip twice during the first 2-3 weeks as I got really drunk and was offered a cigarette. I then decided not to get drunk ( i had a drink here and there but made sure never to get drunk/hammered/whatever) for a month which helped greatly as you are in a clear state of mind and simply saying no is much easier.
Do it man, I smoked for around 5 years too and you'll THANK YOURSELF for it. You really start noticing how much better you feel all of a sudden pretty quickly, more energy. Food that used to taste good now make me jizz my pants, sense of smell has gotten so much better, I recently sat next to someone on the bus who clearly just had a cigarette and I just got disgusted by the smell coming off him worse is the fact that I was that guy for the last 5 years and could never notice. If anything i can see that smell being a major turn off for women whenever you try to get your game on.
I've never tried Chamtix but I do know about it, what you said about possible negative side effects is what put me off a bit worried in case I am part of the small minority who are effected by it although i do know people who have used it with no side effects who said it was great, takes the edge of it big time. What I did instead though was go cold turkey, drink lots of water and buy some St. Johns wort (cant remember the exact one I purchased right now but what it relieves is feelings agitation,anxiety, depression etc. its basically helps keep your mood balanced)
anyway rockstar, go for it and good luck!
ps: that feeling every time you have a cigarette is a feeling you'll enjoy 24/7 as a non-smoker