The plane's great, very passenger-friendly cabin; range and performance as guaranteed, better in some areas, wonderful avionics (I fly the Vision on Globals); great cockpit; pretty short BFL at max gross weight (CS100); but that's not the issue keeping airlines from buying it. The problem is BBD and its perceived poor customer support and questions about the long-term. As someone said, nobody was fired for buying Airbus or Boeing.
That said, the DL deal is a shot in the arm. Along with AC, with a strong oerformance at EIS, it might just get to breakeven.
GF