I'm pretty new to crypto currencies, investing wise.
However, I've done quite a bit of research and starting to investing in some coins last week. Here's my humble opinions:
Bitcoin (BTC): the biggest cryptocurrency, currently has a 40% share in the total cryptocurrency market. It is the oldest cryptocurrency and it still dominates in the market.
Ethereum (ETH): with a total market cap of around $70 billion last year, reached its highest price of $1423 on January 4 this year!!!
Ripple (XRP): best performing cryptocurrencies in 2017 with growth of around 36,000%. It grew from almost $0 at the beginning of 2017 and reached $2.4 in December 2017.
Those are some good numbers I'm seeing and the deciding factors for my investing strategies.
Hope this helps.