1. My girlfriend, I ordered her one and told her if she cant quit I cant see her for the next 2-3 weeks while I quit. So far she has been 6 weeks.
2. My Dad, he has been trying everything possible for the last 6 years to quit, so far he is at 1 month.
3. My Mom, She was only smoking 1-3 a day, and easily converted. 5 weeks.
4. My Sister, I ordered her one and she quit easily since she is not allowed to smoke anywhere near her work, or smell like it. 5 weeks
5-7. 3 coworkers they were all interested from day 1, apparently they had been trying to quit for a few years as well. 1-4 weeks
I think it really depends on the person, If they enjoy smoking and don't care to quit they wont give it the time of day. Anyone I have run across that has tried quitting before and failed, will almost try anything.
And apparently a few others that I do not know, that my family has converted since I converted them.