I've been wondering where to place my extra money, I've researched somehow the 3 of them and have their own pros and cons. Should invest on them?
Electroneum is famous among the people and many of them investing in their money in their token sale and after that.
Ripple is one of top listed in the coinmarketcap site you will be able find their market place supply and their difficulty rate is pretty good. If wish to invest go with this. This is better coin in the list you have in the OP post. Please clarify more about it, and go to invest on it.