Playing on survival mode is one heck of a nightmare...
The following are just examples of what I have ran into so far:
If there is a turret, run.
If there is a mob, run.
If you find a rat with a bomb on it, ticking... run.
When you use a stim to heal, it heals very slow... You literally have to run away and wait for the stimpack to fully heal you, otherwise you have - no chance.
When a car explodes, you die, even when you have a distance from the car.
Getting smacked by the radiated "zombies" a few times, you die.
The pistol by itself is useless during a gun fight with a mob. Your only best survival attempt is to hide and wait for them one by one and use VATS up close with a shotgun to the head, scoring a 95% hit, which gives a 100% chance to incapacitate them.
The "Super beasts" (can't remember the name of them, but they're huge and have big teeth. lol) the mini gun has little impact on them. You will go through at least 1,000 rounds before you take it down. You stand no chance while using power armor. Only way to survive his hide in a building so it can't get to you, and throw the "kitchen sink" at it, while it tries to get to you, but it won't be able to. So, that's your one "cheat" in order to survive.
Survival mode basically insists that you use drugs to get the boosts.
Survival mode in itself on this game is deadly, and I challenge anybody here to try it out. Start a new character and set it on survival mode. See how long you last, or "survive".
The survival mode is how Fallout4 really should be played, because it definitely brings the real life into the game.