well so far, i have got cng from faiz four times and except for the first time(first fill after installing cng wiring back), it gave me mileage of 4.5-5 rupees/km, once and currently i have cng from shell g10 and previous one gave me same mileage of rupees 5/km. Lets see how much this one gives... as you can see there is not much difference in rupees/km of both stations. If faiz was doing some hera phera then it would have turned out to be costly