Originally posted by: PSJ
The Rasengan is better, you can use it in diffrent situations and tactics. Chidori works one way, run fast and dodge your enemy while trying to pierce him through the chest.
Technically rasengan and chidori can be used either way; moving it all around like you do with rasengan, or run straight towards the target like you do with chidori. Seriously, what's the real difference between the two if the method of using them were switched? Rasengan would need sharingan, and chidori would be used freely (as shown when Sasuke used it on Naruto). So there is no real point in bringing up the method of use. The only real distinct advantage rasengan has over chidori is the number of times it can be used. But then again, chidori can be used on multiple targets at once.