RSO: Real Solid Organization.
Member of the Flavor Unit MCs.
The group consists of Raydog, Tony Rhome, E Devious and DJ Deff Jeff. RSO stands for "Rock Shit On". They made their debut in 1985, and signed with Tommy Boy in 1992, but was dropped from the label due to their controversial single "One in the Chamba." They were subsequently picked up by Flavor Unit. But when Flavor Unit ran into economic problems, the group was dropped again and picked up by RCA.
The group later changed their name into Made Men and Raydog changed his rap name to Benzino.