quit and zyban together work very well
I tried Zyban, it made me feel like sh... so that didn't work. I've quiet a number of times over the years, for up to six months at a time. The challenge is not so much in quitting, but in preventing relapse. One puff, even years later, and you run the risk of being back to square one.
The official medical definition of someone who quit smoking is total abstenance for at least two years. Before then, it's actually too early to say you've quit.
Nicotine is a bastard... ☹