I know Warren Buffett isn't a friend of Alts - but he did give some good advice that is applicable here - he taught to buy the market leader in each niche. For anonymous crypto that is currently DARK. The others like Monero are far behind, and even if they have good ideas, either other competitors will beat them, or Dark will simply steal their ideas and implement them as well or better (I have a high opinion of the Dark dev). Either way it's foolish to invest in the distant also-rans rather than Dark, IMHO.