I think the biggest difference is in the damage they can conflict once they've chosen to attack.
I have two labradoodles, each over 80 lbs. We've had them since birth, and my boys (5 - 3) absolutely love them. And the dogs love my boys, too. That being said, the dogs are never left alone with the boys. If I'm not home, wife puts them in their crates or outside. 100% of the interaction between my dogs and kids are with me very close by. They've never shown an ounce of aggression, but I understand they are animals. That being said, if they did attack, for whatever reason, I feel confident I'd be able to break it up quickly with minimal damage, and I'm the definition of helicopter parent when my boys are around the dogs. Never more than a few feet. I couldn't say the same if I owned two pit bulls instead. Even with me that close by, I'd never feel confident in my ability to stop two pit bulls in the case they snapped and decided they didn't want to play with my 3 y/o any more.