According to the teaching, the benefit of entering into high states of concentration is that it helps to calm the mind, developing more tranquility and spiritual happiness. It is believed that by obtaining spiritual happiness then it is easier to let go of the worldly happiness.
Can wisdom be obtained in these states? No, it can't be obtained in these concentration states. If that was so, then when the Buddha went to his first teachers, and entered these high states, he probably would have become enlightened. But he didn't. He realized that these states are suppression of the hindrances. And that you had to do more than just enter into high states of spiritual bliss in order to find true inner peace.
The dangers of these high states of concentration is that sometimes people get supernatural powers and then start to think that they are enlightened. Even if they don't get that high level, we have noticed that for Westerners, even if they get a very low level of spiritual happiness, they become attached to that as the goal.
It is taught that you have to come out of these high states of concentration in order for you to develop wisdom. The classic example is that you come out of these states of concentration, and you start to reflect about their impermanence, about their unsatisfactoriness, because they are impermanent mind states, and they are quite impersonal, they arise due to causes and conditions. They are not yours, they are not me, they are not mine.