The max is 14% more efficient at cruise. The math can be done by anyone with a desire to spend the time. The fuel savings is significant when added up in its entirety. Incredibly significant, and more so with each creep up in fuel prices. Turning off the NG 700s was a very smart move. More airplanes is good, provided you can utilize them at the same rate as the rest of your operation, and with the same load factor. If not, hurts our PS to buy them.