A friend of mine used e-cigs to kick the cigarette habit, in her case successfully. But she said she noticed that the e-cigs she purchased were already preset on the strongest setting when they came out of the package and the hit of nicotine they gave was much more intense than a regular cigarette.
She had to reset them to the lowest setting, otherwise the user would get more addicted, not less.
You can buy very low
3-6mg
In the ultra Europe 50mg
Here max is 15