At some point in time I guess it will become either one thing or the other. It cannot stay both at the same time. Can it? Is it a healthy usage method to have it as both?
In fact, bitcoin is in real a currency and not a investment method. But currently it is more used as an investment method and not as a currency. This is indeed not good for bitcoin itself it if is not used as a currency. Due to do much fluctuation in the btc prices, it is very unattractive to use it as a payment currency. For traders, it is best as they use it as investment opportunity and trade with it.