It does not matter what altcoin you choose to buy. In the future, everything will depend on the theory of probability.
In my opinion, Bitcoin, ETH and NEO look the best coins to invest in for they are of great future profitability and return. I believe if investment is kept diversified by which I mean to say if some one invest in all these coins, he would definitely get good returns in good time. One of the most important things is to know about the technology and market behavior before actually investing in any coin otherwise you end up blaming the technology.