The Q400 compared to the CR9 is a good match. At some point the CRJ will pull out ahead if the distance is long enough. Props are the most economical at the shorter routes >400NM cause that is still well over an hour flight for them. Compairing a SAAB to any RJ doesn't work cause they can't take as many bodies.

A 747 gets better fuel economy than a toyota prius per passenger if it is full. Thats burning 4000 PPH x 4 engines!!!

The only good prop plane for creating a more economical route structure would be like the Q400 with over 50 pax seats.