It is a pity that dobbies have such a bad rep. They are very loving and very intelligent. However, like most big dogs, if you don't know how to train them, then it can become a very unpleasant experience for you with your dog. Dobbies are extremely strong dogs and I know from experience that trying to walk an badly trained dobbie can cause lot of physical injury for yourself and people around you.
If you are a first time dog owner, go for something smaller and easier to control. Once you learn how to get a dog trained, then you can always get a dobbie as your second dog.