This might help you.
My commute is 26 miles each way, each day. 8 miles is 30mph, unclassified and B road, 15 miles is motorway and 3 miles is town.
When I do it in the Jazz, I get 49 to the gallon.
When I do it in the Saab, I get 34 if I stick to 55 on the M23 (tough trust me) but I can have the roof down and enjoy heated leather seats.
Pros and cons. You pay for certain benefits.
I'd choose to use the Jazz more often if I could.