Sir its 10km/l in a company maintained petrol only Cultus with A/C and heavy traffic jams in evening.
The engine response and acceleration are much better then the old carby one and best of all that whinning noise is not there.
Some people have faced issues on CNG though.
BTW, It also gets a Pioneer MP3 player compare to crappy cassette player in carby Cultus and footmats are nice.