I don't think Bitcoin or any other crypto is an investment, it's a speculation. Beside popularity we don't have any other way to valuate it. It does not have earnings per share or book value so we can gauge/measure how fair its priced. Nor it's a currency of a country where its price determined by country policy or financial condition. crypto currencies are mare speculation. Its merely driven by popularly and scarcity or say demand & supply.
Don't expect these crypto currencies will overtake conventional currencies. No country will allow that its currency to suffer due to a fake (not a legal tender) currency. Easy access of these coins (Cryptocurrencies) increase the fear that these coins can be used in terror funding. WannaCry is a real example if you are still thinking. If such incidents increase federal banks will have sufficient reason to impose some restriction on these coins or in worst case complete banning these coins.
Technically speaking I expect Cryptocurrencies rally will fizzle out in a month or two. You cannot expect such a wild rise for a long term. You can hold your coins for now without fear. But make your mind that you have to exit in near tern in order to lock the gains. Treat it just as short-term opportunity.
Disclosure: I/we have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours.