"But who has the courage to keep a position for a year on those markets?"
Those markets would be lucky to see that kind of return but not everyone can take the risk. I think about this every time a yearly percentage growth is referenced. When the measurement of a coins increase in value is 10 or 20x it's done in hindsight. The question is could you hold onto something after its doubled or tippled. Price predictions get people in this mind frame of numbers being associated to somethings value. With XRP in particular, it's value is realized by the customer when they use it. Sure XRP will have a price at that point but will it be 30x or 1,000x relative to now? Who knows. If you're in it for the USD and you are looking for a good time to take profits, sell a small percentage of your XRP after an event happens. Measuring XRP's value to it's functional use will be far more rewarding than selling it based on price movement. That being said, I can see XRP between $17 and $22 during 2018, but I'm still not selling.
With anything I think is a sure bet I do my best to play devils advocate. Why would XRP need a fluctuating market price? If Ripple wants stability why not build their networks and platforms the same way and just peg XRP at $100 or $200 and let the banks and FI settle transactions at that price. I am all for free markets, but in XRP's case, what value does it lend to the tokens function as a tool for cross boarder settlements?
RE: Why in 2018 will XRP still be better than the BTC?