It has the engine of aircraft which is lighter with great output. still milage is not at all issue at all let me compare with some piston engine.
MAZDA RX-8
1300CC Rotary Engine which produces 228 BHP Doing 7.65KMPL, Kerb weight =1354KG
BMW 5 Series
3000CC Piston Engine which Produces 215 BHP Doing 8.07KMPL,
Although i compare 2 cars of totally different class hmm here I goes for another one more competitive car.
NISSAN 350Z
3500CC Piston Engine which produces 300BHP doing 8.07KMPL, Kerb weight =1550KG
Look almost same Milage that 200KG more weight in 350Z leads to very little over all difference. but mazda rx-8 is very unreliable accoring to different sources although it out class 350Z in driving dynamics.
Sorry i forget to mention nissan being 2 seater 200 KG heavier and mazda being 4 seater being 200KG lighter