Although, there exists a con: Cryptocurrency as a whole is gaining a "dirtier" reputation thanks in part to it's new-found use as a black market medium of exchange. People had a vision of Bitcoin being an easy to use, mainstream currency for the general population (pipe-dream in my opinion) It is clearly not going in that direction.
Governments can very easily outlaw Bitcoin if they so please at any moment. Any legitimate exchanges would be shut-down, no LocalBitcoin, no Bitcoin ATM's, no BitPay, no NewEgg and Overstock accepting Bitcoin payments, banks ceasing operating with Bitcoin copmanies (good luck converting to fiat)