I used Chantix but I am wondering why you are going
with the gum? I have no personal experience
with it, but I do know many who have used it, are still using it, even many years after their quit. It appears that it's a trade-off in addictions. There was also a thread on here about the gum. Here is the link to it:
http://www.medhelp.org/posts/Smoking-Addiction/Effects-of-Long-Term-Nicorette-Use/show/730769?post_id=post_4517392
Make sure you research the alternatives.