These streaming servers are all ok if you got good internet, but not everywhere has.

I have tried PSN Now stream a game on a 350Mb down and 30Mb Up and it lags at parts of the game when it loads (you know the most important bit), also heard Google isn't that good at the moment either.

Haven't tried xCloud but a friend is on the beta and said stream from xCloud app on his phone to his Xbox One seems stable locally and remotely, but at a guess there not a lot of users using it.