Both are difficult to get into, but I hear you cannot do wrong with either. Good idea to start now to secure a place. I think they are both considered 2 of the best in Doha. If you are an American, you might prefer the American school because it would make it easier to transfer in and out since the system is the same. And the American school is, well, more "American". Depends what you are looking for. I'd say talk to both of them and see what you like better, maybe you will prefer one over the other once you find out about the curriculum for your kids' particular grades.