I've only taught at flight safety or more accurately, used there equipment while teaching, but have done an initial type at CAE and word on the street is that Flight safety is a little better in some aspects. However, I really enjoyed my time at CAE and learned a lot. Maybe it's best to say that there isnt that much difference and both have great instructors and equipment. Ive only fown one bizjet so my opinion would be worthless on which is hardest.