"How long should my essays be? Use your best judgment in determining the appropriate length for your essays. You should try to tell your story as succinctly and as thoroughly as possible. Keep in mind the large volume of essays the committee members read."
That said, I'm applying on-line. And I'm sure the boxes in which you paste in the essays are not infinite in size. So write more if you have a lot to say for a particular question, and less for some others.
If you are using the online application, the word limit for Essay #1 is 500 or less. There is no limit on the other essays.  lease feel free to contact our office if you need further assistance.
Janchen, Campus visit is always positive. Every week, we have prospective applicants sitting in our class to have class visit and some interview. Normally, Admission officer will have a formal interview after class visit. If you were in states, I strongly recommend visiting school.
Questions will be very normal, such as Why MBA, Why Darden? Good luck