It will improve crippledad. As I said earlier in the thread, mine wasn’t the best until it was run in at around 5,000 miles. It now consistently returns 30+ MPG around town and near 40MPG on a run which personally I feel is more than ample given the engine size, performance and size/weight of the car.
Even if the fuel economy hadn’t have improved, I would have still been more than happy as the engine really is that good. We have a 2017 190bhp 2.0TSI Audi A3 as a second car and that engine feels is awful in comparison.