Ripple was not designed to be a currency like Bitcoin or Litecoin. It was created as a highly efficient transaction system for banks, and it excels at that. I wouldn’t rule it out that XRP might be pumped by Ripple, because they certainly do have that power. They could also dump the price.
The fact that the Ripple price is manipulated, probably everyone should be convinced of it. Any centralized currency can be created in any amount and I'm sure no one will ask investors for their opinion. If someone succeeds and buys before the pump, he will be lucky and earn money. However, if Ripple decides to increase the total supply, the price will automatically drop. Investing in XRP is simply a lottery.