see to sing a jazzy number include lots of variation in tones and lots of energy is required , as compared to nihira who can only sing classical kind of songs but himani has variation .
secondly if u notice himani she sings with great ease and is free singing , she is way ahead of himani in my opinion , even though i like nihiras singing too but my vote is for himani because of her gifted talent.
singing in sunidhi style is not at-all easy let me assure u guys!!!