Why buy 0x?
1) When Amp is used as collateral, every asset becomes a fast and secure medium of exchange.
2) The supply of AMP tokens is fixed at 100 billion AMP. The AMP token is up 581.7% in the last one year.
About 0x
1) How 0x works is a combination of centralised and decentralized exchanges. It draws from the best of both worlds: it cuts out third parties through smart contracts which ensure users are in control of their funds, yet maintains the lower costs associated with running centralised exchanges through something called off-chain relays.
2) 0x tokens (ZRX) are used to pay the relayers. They can also be used to vote on 0x protocol improvements.