I promised some time back to document the actual real world fuel consumption of the new E92 M3 versus my previous E46 M3, so here goes ...
Old M3 with > 80,000 miles was averaging over 28mpg on my daily commute from 18 miles West of Glasgow into the city and general running around with only the occasional thrash to the limiter in each gear.
New M3 with > 2,000 miles is currently averaging over 24mpg used in the same way.
I was sure I read somewhere that the new car was to be 15% more fuel efficient due to the new technology (brake regeneration etc.), but maybe I just imagined that
Anyhoo, I'm pretty happy with this given the additional performance
I also recall that there were a few brave bets on the outcome of this, so I'd be delighted to hear if those bets are now going to be honoured ....