Laser hair removal (whether it is LASER or IPL), cannot ever be guaranteed to be 100% permanent. Our bodies are truly amazing, and have the ability to generate new hair follicles. Some people are lucky and get little to no recurrence of hair growth, but the greater majority of people will have to do maintenance touch ups about twice a year (sometimes only once in a year) after having completed their treatment course. In some cases, the regrowth of hair only happens later in life with hormonal changes, or with pregnancy, or if the person develops hormonal conditions such as polycystic ovaries, etc. So to answer your questions, LASER hair removal would give you a longer lasting result, but you would need an occasional touch up. IPL will also give you great permanent hair reduction, but you would most likely need more regular touch ups than what you would with Laser.