the answer are both of them. why? just because dont put all egg in 1 basket. simple rule for trader. for me I like ETH more than Ripple because ETH is a good platform to do many things on it
I also think better buy both. Ripple is always following the Bitcoin. If you dont want to buy too much bitcoin, you can chose ripple. And ETH is competitive with Bitcoin, so of course you should have too. to avoid a lot of loss when bitcoin team falls. (BTC and ripple).