The greatest Rotty to ever live was my uncles dog, Puppy... ok his name was Lord Apollo of Finwood, but we called him puppy because he was. He would sleep with his head on my grandmother's lap in her bed while she watched her stories. He loved everyone. A dalmatian killed him. Of all the dogs, a dalmatian..
My point is that any dog can be mean if it isn't raised right. Sadie, my Pit, loves EVERYONE (and adores cats). It's partly because my family and I are very friendly people and partly because she is properly trained and obedient. People who have large, powerful dogs should train them, no matter what breed they are.
Sadie and her best friend, Tyrael