They're satisfied with life, have fewer regrets
                                
                                
                                    (Newser) -
                                    Heavy metal was the No. 1-selling music genre in 1989, and parents feared the worst: that Satan worship, drug use, loads of sex, and suicide went along with it, write researchers in the journal  Self and Identity . Records were burned, "Parental Advisory" warning labels were born, and some '...