Eth is no doubt one the best long term investments for the long term taking into account the value it brings to the cryptoworld . At the moment it is going high & should cross $500 soon and then return to stablise around $430.
But in the long run, it one of the best coins after Bitcoin.
Eth is really good for long term invest but it may not the best coin after Bitcoin, i think still can not say which coin is the best after bitcoin because bitcash and neo can still replace eth.