I took it for depression only - I was not a smoker.
It didn't seem to work for me, as I had hoped it would. I had tried a few of the SSRIs (Prozac, Zoloft) and didn't really respond to them, so I tried the Wellbutrin because it works differently, yet I still didn't seem to get better. In fact, that was one of the worst episodes in my life and the only time I actually made an attempt on my own life.
I also tried Effexor, which is a combination of SSRI and another neurochemical regulator, but it gave me wacky dreams and I couldn't get a good night's sleep.
What works for one person will not necessarily work for the next one. It depends on your body chemistry and symptomatology. You know that it is safe for you, as you did not have side-effects when you used it to quit smoking, but you need to know that it's not going to make your problems go away or turn you into a happy-go-lucky person. Just think back to your emotional state when you were taking it previously, and that's about what you can expect if you take it now.
Also:
1) how old is the supply you have left? It may not be effective anymore if it's over a year old
2) Has your health status or other medications changed since you took it for smoking cessation? If so, you really need to check with your Doctor before taking it again.
Take Care, and Good Luck!