Still yet to get my Scangauge and this is only my first recorded instance of average MPG but it's looking good...
44.9 (UK) or 37.4 (US), that's 33.5% over the US average for this model.
Not a bad baseline figure although obviously a few more records plus cross referencing with the Scangauge will help paint a better picture as I'm not usually found driving 160+ miles of motorway!
Still, it's a good start and very encouraging.