[Folkie]

I've put 3600 miles on my S5 in the first month and I've found that the mileage has improved over time.

On a recent 600 mile trip, with the cruise control set to 75, I got 22MPG (US) . This should be about 26MPG (UK)

I'm now averaging about 18 MPG with mixed driving

 

[Folkie]

What did it do when you had a lower mileage?

Hard to tell, as I was breaking the engine in.. It was never over about 18 (US) mpg, averaging about 15.