That's definately a bit on the portly side, but without vibration concerns, a lot of weight can usually be saved. My Larger E3D's for instance are 1640 squares, 90 inch span, and only 9 lbs flying, including a pound of motor and 2.25 lbs of battery. I saw that carbon (might be fiberglass, dunno) tube "runners" were used in the fuse of the frenzy. Very nice. Seems so obvious but I've never thought of doing that. Good strength with hardly any weight, gotta remember that
Very interesting design.