I know that I would not want to hold such a coin for even a second, and taking into account the draconian control of the people the Chinese want to have it is unlikely that foreigners are going to be allowed to hold it either.
It may definitely add a certain degree of usability versus their regular currency, but that's not even the point. Bitcoin offers a constantly increasing market, and the most important aspect is that it allows us to store value outside the governmental and banking system. You can spend your value whenever you want, where you want, and at whatever quantity you want -- no one can block anything, and you don't have to justify anything. From there it's safe to say that even when they enjoy a great level of in-country usage, these national digital currencies will never be a threat to Bitcoin or basically any other crypto currency.