In 6th they were a mixed unit. In 7th (and 8th) they were a single unit without gors.
I have 11 ungors, 15 gors, 15 khornegors, 5 centigors, 3 minotaurs.
I bought them when it was possible to have a mixed army, and I wanted them to go with my khorne themed chaos warriors. All axes because its khorne's weapon!