When Ethereum came out, it was looked down upon because the market hadnt matured yet. No one understood much about cryptos beyond the peer to peer transfer. When the difference between Bitcoin and Ethereum was established, that is when we had a surge of the altcoin rush. This caused prices to skyrocket on all altcoins. It seems as if the roles have been reversed and there is more doubt on Bitcoin than anything else. This is why we recommend you hodl Ethereum over Bitcoin.
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https://usethebitcoin.com/will-ethereum-better-investment-bitcoin-2018/I think both will do good this 2018. Eth has good foundation that is why it is stable. Bitcoin is doing strong the problem is all the bad news and people being afraid and panic selling. But left alone it will go up non stop. And it wont go down because of all the investments that will come in.