I didn't apply to Mannheim because I thought it was not worth it. And I did not consider Aalto at all, so I cannot say, I don't know the faculty! But I can ensure you, that the marketing department at IE is good and IE is especially known for enterprenership, so hopefully also the management faculty is good! They are very easygoing so just ask them who could be your supervisor. I also think that having flexibility is totally good for research, don't look at it as a weakness. Your research interests will develop so it will be good to work with more than one person. You might want to ask Aalto about this. And also, look at where your supervisors are publishing (which journals). In the end, it is the supervisor that makes the difference!!
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