@cahillr2: The 3 Whys are always there, so good to be prepared for. Also, other questions that I was asked by both interviewers were: culture shock related (though these come up more in a conversational way), what other school you applied to (this is to see your research process and to double check your "why INSEAD" answer), and also questions and discussions about the workload. The latter came up for me in both interviews, again in a conversational way, more in terms of them sharing their experience, I'm not even sure if it's an actual question or a coincidence.
Overall, my INSEAD interviewing experiences have been amazing. Because the interviewers don't have our essays, it's basically been just relaying to them the same thing I wrote in my essays (especially essay 1 and 4).
Good luck!