Having lots of chakra doesn't make you automatically powerful; for example - Genin Naruto had more chakra than Kakashi but was he stronger? No.
Genin(part 1, because he's still a genin...More like a sage, but whatever...he probably has his own title now) Naruto just had more stamina than Kakashi.
He couldn't produce more chakra than Kakashi, though...
He sucked at producing chakra.
And more chakra = more power. Because that's what power is...
But even if Naruto could produce more chakra(and use more chakra to individual techniques without wasting) than Kakashi in part 1, Kakashi was more much more skilled, intelligent and experienced.
Power is one thing. The Ichibi, for instance, is more powerful than Jiraiya.
But is it
better? Is it
stronger, considering everything both have to offer?
Jiraiya is a better fighter. That's why he'd win.
You could have an insane power and yet not control it very well...
Kyuubi was talking about Sasuke's chakra being sinister. Not something related to quantity of chakra.
How could you say: "Your chakra is bigger than mine"?
It makes no sense.
You produce chakra.
You don't have a chakra reserve like people are talking. You have stamina(which is physical/spiritual energy).