Early charismatic Catholics were not heretics, and some of the larger communities in America had representation to the Pope in Rome. Even though some dioceses have an office and a person in charge of charismatic renewal in the dioceses, the abuses continue and add to the confusion of many adults.
Not too many young people of the Neo-Conservative Generation are interested and good thing, too.
Here are some of the dangers--only some:
no authority
women in charge
so-called deliverance and exorcism outside the authority of the Church
no accountability
sloppy and abusive celebrations of the Mass
the laity saying parts of the Mass only the priest should say
uncatechized groups which have not read nor will not read the CCC
a sub-culture of healing and semi-new-age activities not in keeping with directives from Rome
an over-emphasis on experiential religion
anti-intellectualism
false ecumenism
a strong dislike and even hatred of the TLM
a false idea of prayer and suffering; even a denial that suffering is necessary for salvation
the idea that Confirmation must be re-done in the Baptism of the Spirit-heresy
a blind acceptance of apparition, visions, and other spiritual manifestations
and many. many more