I wouldn't run full hydro on something you drive on the street. It may work fine if it's set up correctly but if something breaks or fails you will have no steering, for that reason I wouldn't run it on the street. On the trail I would preffer full hydro over ram assist.
I have read some posts that you can still turn when motor not running but VERY stiffly.
It almost seems like there is less things to break on a full hydro than on a cross over steering with hydro assist.