I still believe that PoW is superior, in any case when a coin is used as a store of value. In case of PoW the security adds up when a block gets older, in case of PoS this not the case. Also PoS makes the rich richer, what leads to centralization over the long term. PoS still have to be proven at scale and I think it will fail. I think finally there will only be one huge PoW chain and all the other chains will use the security of this chain. I know I will not make myself popular when I say this, but I think even Steemit will finally fail because of cartels of wales in the PoS system.