Hi just wondering if anyone could tell me the differences in the difficultys, do you get less loot, ammo, health, ([censored] dark souls cant save,restart if you die crap)?, thanks

I haven't tried any of the other modes but I've been playing Nightmare mode right off the back and I have to say I love it. I don't know if it is the mode or not but the AI seems more combat aware, flanking you, flushing you out with grenades, I have even heard npc's yelling to each other "Ill give you cover fire while you push him." And sure enough one dude will just start spraying at me while the other tries to rush up closer. Not sure of that is a difference that the modes make, or if the rest are that way themselves. I haven't died a lot, but I sure do have to think out the situation and use tactics of my own to get the upper hand.