Here are the advantages of Bitcoin:
1 totally decentralization,there is no issuer of bitcoin which means no one can control the gross amount，it is fixed by a P2P arithmetic.
2 anonymous,free of tax,no supervision
3 robustness.Bitcoin exists by P2P network and there is no issuer,so it cannot be shutdown by external force.The market price of bitcoin maybe fluctuate or even crash,governments may announce it is illegal,but bitcoin and bitcoin network will never disappear.
4 no countries.If you do an international wire transfer,the records will be saved by many institutions.But if you use bitcoin,just input a bitcoin wallet address and click the mouse,your money will transfer successfully after few confirmations of bitcoin network.
there is no record left in some other place.
5 Altcoin will be hard to exist.Because bitcoin is open resource,anyone can creat a new currency likes bitcoin.But these altcoin are all weak,anyone have enough arithmetical capability can destroy this kind of altcoin easily.look at bitcoin network,it is huge now and no one can destroy it.