The mere act of using the vapor gets you over the psychological effect of not smoking.
I just used a basic vaporizer. I did find out that the bottom loading tanks just suck and for some reason you end up inhaling fluid. So I prefer the top loading tank
as far as liquids go. When I first stopped buying cigarettes, I would buy the heaviest nicotine liquid that I could find, but I also bought a bottle of zero nicotine fluid. Then as I went for refills I would mix the two with less and less nicotine.
Personally stay away from the flavored ones if your a smoker, because the flavored ones will make the act of smoking more pleasurable. I tended to smoke flavorless ones. If these was a flavor called hobo's butt crack, it would probably really make you stop smoking.
Also I tend to replace the tank once a month just to make sure that I'm actually getting vapor, if you don't eventually your not getting anything.
Right now a bottle of fluid runs about $10.00 and took me a month or more to get through. A basic tank will cost 8 to 10 bucks.
Also its best to also buy a second battery, if you're using a vap to stop smoking and halfway through a work day you run out of battery power, you'll end up buying a pack of smokes.