I'm getting near on 39 mpg out of the 328i with an even mix of town/country lane/dual-carriageway driving. Mostly in Comfort but with sessions of Sport/+ when I haven't got SWMBO on board
Also managed 50.9 mpg on a 300 mile motorway run.
Get the impression that I'd get +5mpg or more in the 330d with the same sort of driving.