I have three lines of Bandeds:
Diesels - Co-Dom with super
European Banana - Stephan Broghammer's stock (Germany)
Oscars - Our own line from CH's these guys are genetic as in they pass the trait on but It's not co-dom or recessive, just some of the babies come out banded, the nicest Oscars come from Oscar x Oscar pairing but it could just be characteristics passed down from parents, rather than a predictable recessive or co-dom gene