Datsun Go+ is fantastic car for fuel efficiency. I have driven it from Jorhat to Sivasagar and back to Jorhat (approx 100 km) at a speed 50 -60/hour and found 25km/ltr average.
Its engine sound is very smooth and noiseless. In Datsun G+ the third raw seat is unuseable because adult is unable to seat hear. It may be usefull for kids only.