Mike
Just a quick note that may interest you:
I have just driven down to Monaco in the blue 456; 930miles door to door. The car was fabulous, went like a dream! Very happy with it!
Best Regards
Edward
Approximately 15.5mpg - however note that the air con was on most of the way as it is very hot here. This corresponds with the figures quoted in the manual which is 8 - 20mpg