I always find a small amount of humor in these types of questions. This isn't like comparing a Georgetown and GWU or a USC and UCLA.
Very similar schools, in the same area with similar academic standing.
The only similarities here are they are exceptional schools 3 hours apart. OK, OK, 4 with D.C. traffic.
What kind of college experience do you want? What type of environment will you thrive in?
One is extremely structured, planned, and executed. You will have relatively few decisions to make with limited freedom. When you sleep, eat, and study is largely part of a schedule that is set. Certain people thrive in this structure, they expand themselves with the extra time created by not having to work, cook, do laundry, shop. Where else will you get to go to school, for free BTW, where you have a single mission, self development professionally and personally to become a leader?
You will be going to school with other service oriented like minded people. You will develop bonds that very few people could ever understand. You will forever get to respond "Annapolis" when asked where you went to school and see the reverence in people's eyes.
The other you are on your own. You have to decide where to live, what/when to eat, when you shop, study and yes even do laundry. Frat or Sorority, you decide. Drinking on a Tuesday night, going home for the weekend, what to wear to class, you get it. Don't want to go to class? No one is going to say anything. The unit will monitor your academic progress and get in your grill, but typically after the fact and sometimes too late. You will likely have to incur some debt to cover room and board or dedicate some of your time to working.
You can choose to make military a regular part of your day or you can be a ghost MIDN, participating only when required. Although ghosting as a MO is much harder.
You have have a wider variety of classes to take, a much more liberal student body, a wide variety of diverse thought and some who will not like you because of your choice to serve. (This is much more rare today then in days past, but still exists.)
Common ground? Not much except as an MO you will have to complete Bulldog at both schools and owe 4-8 weeks the other summers for training.
You can't go wrong with either choice. You need to decide what you want out of a college experience. Visit both of you can. Talk as many MIDN at both schools you can. Then go with your gut.
Congrats on your success!
OS