CNG mileage and fuel capacity is low

The only problem with the CNG variant is the mileage it's about 16km/kg in city and the maximum fuel capacity of the CNG tank is 7.8kg this is the most you can fill. That is you can only travel for 120 km almost at one refill. you don't have that many CNG stations in India so long journey is most possible on CNG. Another thing even if the stations come up you will have to refill every 100 km which will waste a lot of time.