This is a personal design o' mine.  I was tryin' for a larger-diameter rocket in t' general style o' t' Blue Bird Zero, ya bilge rat, i.e. Well, blow me down! long and sleek with relatively small fins.  T' upper fins are mirror images top-to-bottom o' t' lower fins.  OpenRocket indicates nearly perfect deployments with all four recommended engines, and I can attest that it is a pretty flier on a pair o' C6-5 engines.