Autocar last week did a comparison test between a Lexus GS450hSE, (hybrid) BMW 535D (diesel) and Merc E500 (petrol) Each was meant as an example of a 'state of the art' power unit in a luxury car. All were of course autos. As expected, the 5.5 litre petrol Merc had the best performance and by some margin. The BMW and Lexus were very close. But it's - as usual - the fuel consumption in the real world that is of interest. Here are the results starting with the official government ones.
BMW Lexus Merc Urban 25.9 31.7 16.7 Extra Urban 44.8 39.2 34.4 Combined 35.3 35.8 24.6
Real world:- Town 18.7 21.7 13.7 Motorway 31.0 29.0 20.6 Country 27.5 24.6 20.0 Test overall 26.3 25.9 16.3
So as usual, the 'official' figures bear no relation to real world driving conditions, and favour the hybrid.