For me, bitcoin is much better than the real money at the moment. Because of the volatility, it became an advantage of bitcoin to other real currencies. It also became an opportunity for everyone who wants to earn or to have savings in the future as well. This might be the reason why it became big to them although so far it was a virtual currency.
In investments you can actually fiat many has wide range option since you can use it everywhere but if you mention on trading well bitcoins is totally good since the volatility is much promising compare if you trade it on fiat currency. But this talks about bitcoins comparison, growing up and other is long discussion since actually we don't know how things will go if bitcoin can even hold his dominance in future.