To me, Monero is clearly the best.
Sorry but Monero doesn't have added functionality like Deepvault found in DeepOnion. And DeepOnion is building on their crypto creating smart contracts (Something Monero doesn't have). This speaks to the strength of ongoing development taking place in DeepOnion as compared to Monero.
For me there is no comparison, DeepOnion does everything Monero does.... Only better!
what about the fact that most of the coins is owned by one party. imagine in future price grows very nicely and suddenly they want to dump their coins?