How can any one give this very flawed product 5 stars? Reading through the past comments, and my own experience, 5.1 will lock up. 5.0 being, for now, the only safe alternative. So for those who give it a 5 rating (and still report it has problems !) you are not doing the Mac community any favours. All you achieve is to push up the average rating for what is a typical Microsoft release, untested and flawed.