Only just found this thread.
I and my husband have been none smokers for 18 months thanks to Champix.
I was a 30 a day and husband rolled his own and went through a pack of tobacco a day!! yes really!!
We have both smoked for 40 years, the only time I didnt was during my 4 pregnancies.
What I can say is that it is the best thing we did.
For those doing it, I really is worth it. If I can give any advise it would be to continue with the whole 12 week course even if you think you have beaten it. I have heard that its a higher percentage of people wo restart after champix are those that do not complete the full course.
They did make me a bit nasty/short tempered for a while. Disnt effect husband at all in any negative way. But I have a history of depression so maybe that was why.
My friend who tried champix found that alcohol affectd her more than usual, she didnt think she was drunk but would wake up the next day with a hangove and memory loss, she stopped taking them because she felt like she was going mad.
They are a fantastic aid but I firmly believe they should always be prescribed and monitored by a GP.
Massive good luck to all trying to stop, well dne for all those that have managed it.
Oh and since stopping I have had several stress factors which normally would have me reaching for a cig.
Family member suicide.
Sudden death of my great neice (2)
Some very distressing events regarding my grandaughter
organising 2 daughter weddings within 3 months of each other.
2 bouts of severe illness so several weeks off work.
Several parties and a friends death
an STILL A NON SMOKER 
yep champix is the biz!!