Just wandering around and I skimmed through this thread and there are a couple of points that were made that I'd like to address.
1. It isn't stated anywhere that Kushina's chains have anything to do with her chakra's specialness. It is much more likely that they are some form of sealing...
Re: Naruto 505 Discussion/506 Predictions
Naruto HAS to throw his RasenShuriken, it'll screw up his hand if he doesn't since it's a double edged sword.
In any case, I don't think Naruto will be using Sage Mode for awhile after he masters use of the Kyuubi chakra. Comparing the Kyuubi chakra...