I love taking dogs in the woods, and it's where they like to be.
I started out young, when I was just a wee lad, we had a silver shepherd (Gretchen), and a Newfoundland/shepherd (Heidi) mix. They were a great pair. Whether it was hunting or protecting me from problems, they worked as a pair. Gretchen would raise 9 kinds of hell, and Heidi would stalk in behind whatever it was, and then give a low growl or pounce, depending on the situation. Can't say if they ever saved me from anything, but I'm sure they nipped some potential situations in the bud. Keep in mind, I was very small, maybe an inch taller than Heidi (who was friggin massive). One time in particular I remember was coming up on a strange looking, dirty guy in the woods (or rather he came upon me). Gretchen got in between me and him and bared her teeth and started barking like crazy, Heidi disappeared. A few second later there's this low growl from behind the guy and he turns and there's all of about 200 pounds of Heidi standing there. I remember telling him "I wouldn't run if I was you Mr. I'd just walk away slowly." He did.
Most of the rest of the time, they'd kind of herd me, if they didn't want me going somewhere, they'd nudge me in a different direction, and if I insisted, Heidi would flat out just block me. I have very fond memories of those two, and as an adult, understand how much they protected me. I guess they treated me like a puppy in the pack.
Chopper, my mastiff/shepherd mix in my sig line. . .he's a handful. I love that dog to death. He's smart, aggressive and tough as nails. I like the big, aggressive dogs. Only one real story with him, but I think too many people here would have their panties twist up if I told it, so I won't. Most of the time, I just trust his "doggie sense", if he's relaxed, I'm relaxed, if he gets tense, or doesn't want to go a particular way, I just trust it and go somewhere else. We also work as a team when hunting (when legal), and no, I don't use him to drive deer or bay hogs. He can smell prey before I know they are around and he will often run interference for me, sometimes take them down himself (not hogs, I taught him real early not to mess with them). He gets his share of the kill.
One word of advice on the big, aggressive breeds: learn to "speak doggie". What I mean is, run the relationship like you're part of a pack with it. Make sure there's no doubt that you're the Alpha male. As tough as it may be, sometimes you have to be really hard on them as puppies to train them right. Also, be prepared, they will challenge your authority from time to time.
A couple things I do when I get a puppy is instill that they have to obey me above all else, or there are consequences. There are also positive consequences when they do obey me. I also reinforce that they do not have to obey anyone else.
Another thing I train them is how to use their paws like hands. When they are puppies, I'll pick them up and push on their toe pads, and then start wrapping their toes arounbd my hand and show them how to pull it towards them. Then I give them little puzzles, like put a tennis ball or biscuit under something and show them how to reach in and wrap their paws around it and pull it out. Comes in real handy for them later. Although I get worried that they will get that doggie epiphany and learn how to operate the refrigerator door. . .