The cruise control is wonderful, especially to improve your mpg. But I would try to hold off a little for the first few hundred miles. Reading the running-in wiki suggests that constant speeds are not the best way of covering the first few hundred miles.
Up to you how you run the car in, of course, but may well be worth a good read of this:
http://www.civinfo.com/wiki/index.php?title=Running_in
I have done about 1800 miles now and the mpg figures are still improving.
Enjoy
