So, I got the chance to play Survival Difficulty for a while and let me tell you guys, whether you enjoyed the game or not, this is going to feel very grindy. Wait for NG+ if it ever releases or take a big break before going at this again if you've recently finished the game. If you don't, it's most likely going to feel like a chore.
This is what I've noticed.
You die in three hits
No HUD whatsoever, nothing
No Fast Travel
No Survival Vision
Impossible to change the difficulty as you play
No load-out from previous saves
Expect another 80 hours.