According to no less an authority than the RIAA, Boyz II Men are the most commercially successful R&B group of all time. They sold ludicrous numbers of records and were involved in three of the longest-running number one pop singles in history, and they did it as a unit of equals. In fact, their four-part harmonies blended so smoothly that most of the general public would be hard-pressed to name any of the group's individual members. And that's no reflection on their skill as singers; Boyz II Men were among the first male R&B artists to adopt the sort of hyper-technical melodi...