An ENTJ with a vision is a powerful and a great leader. To share a positive experience, I work closely with an ENTJ, and I have never enjoyed working with anybody like I do with him.
He's direct, straight to the point, very strategic, efficient and I enjoy brainstorming and planning with him. He's reliable, if he gave you his word he'll keep it, if he can't keep it he'll let you know. I don't have to worry about butting heads with him, or stepping on toes. We can get to the heart of the issue without wasting any time, and come up with good decisions and solutions. However, he's widely misunderstood among his team. Because he has such high expectations of everyone else, he comes off as unapproachable, intimidating and very demanding.
One thing he tends to do, and I can see why it would upset people, is sidestepping someone and taking over their task if the task is of great importance, because he thinks he would do a better job, or because he sees that others don't understand what he's getting at in terms of goals to be achieved.
He doesn't it know, but he taught everyone else how to own up to their responsibilities, and how to be a lil ambitious. From the day we started working till now, our team dynamic has changed a lot because of him.
Actually, I should tell him that one day. =)
The thing about ENTJs is that they care differently. This guy will not comfort you in words, but will do something about what's bothering you, and he's been a great help to me, and whoever else who have worked with him.