I am evidence. Over 4 years of it.
I have made 2 daughters and 2 sons evidence of 2 years
I have made my ex and his brother evidence going on 2 years now (both may I say have been able to be taken off of blood pressure meds since stopping the smoking)
I would like to add that is quite a few provaris to loose trying to convert people, but in the long run it has worked when nothing else has. Well worth it to me.