fake cigs

does any one know about the battery operated fake cigs like crown7 or njoy brands??...And do they work?? They are supposed to be nicotine free and vapor instead of smoke, harmless...I stoped smoking almost 2 months ago but i was wondering if these "safe" alternative smoking devises are really all that, or if it would make me want to smoke again a real cigarette?...Any advise would be greatly appreciated.

thank you
Gloria