Originally posted by: Mut@t@
rasengan isn't about how much chakra is used, it's about how you manipulate the chakra. that is why naruto was able to attempt at it so many times during his training.
That is why, in my opinion, it makse for a more powerfull and efficeint jutsu then Chidori, CHidori immits large ammounts of Chakra, but can only be used a certain number of times, whereas Rasengan doesnt and as is evidence of the roof encounter,ransengan is more destructive.