Mileage on highways is 250km on a tank full (approx 10/11 kg cng). In Delhi it lasts around 120 to 140 kms (never paid much attention to the city mileage).
Petrol mileage - highways = 14/15. City = 8 to 11kmpl.
Amongst your options, Im slightly biased towards Corolla, but I havent heard much about its cng performance.