I would always go for Cardano. I am not a very big fan of Ripple and I am very uncomfortable about its association with the bankers. On top of that, I have a feeling that XRP is much over-priced right now. On the other hand, Cardano has a lot of future growth potential, as its technology is quite solid.
That ripple that cardano both have a sturdy construction, the only thing that sets them apart is the idea. ripple idea is more like me it will be used...I can't say that about cardano.