Adolescent preferences for non-mainstream types of rock music can be markers of adolescent problem behaviors, but no study has ever investigated whether this relationship continues into adulthood. In a six-wave study, 900 Dutch adolescents were followed from ages 12 to 21 (Mage T1 12.4, 51.1% girls), while reporting on depressive symptoms, mental well-being, aggression and drug use. A latent class growth analysis on their preferences for specific types of rock music revealed four fan groups. When these fan groups were compared to one another, in adolescence, the all-out rock fans displayed the highest peak in depressive symptoms and the lowest dip in well-being and the rock/metal fans reported the most aggression. And for both these groups, drug use increased at the onset of adulthood. Pop fans displayed a profile characterized by low depressive symptoms and aggression, and high in mental well-being. Finally, the popular rock fans held an in-between position between pop fans, on one side, and the all-out rock fans and rock/metal fans, on the other side. Thus, music preferences can be markers of problems, not only in adolescence but also in young adulthood. Still, music can enhance mood, helps to cope with problems, and peers in fan groups can provide support. This research focuses on the relationship between music and problem behaviors, specifically among members of the all-out rock fans and rock/metal fans, but many of these young people might have had more personal problems if they had not had their music and their fan-group peers.