We stayed a couple of nights at the Marriott. The best thing about the property is the beautiful view of the water from the waterfront balcony rooms. The sunrise over the water was spectacular.
As noted by others, the location is also convenient. You can easily walk to the Naval Academy.
The rooms themselves are definitely not worth the $300+ rate. The toilet tank had a small leak. One of the hotel staff greeted me with a "how is it going buddy." Even though charming, a bit unorthodox. We waited for the room service for over an hour. I called the front desk back (which also took orders for room service) and they told me that they had sent the order to the wrong room, despite them having the room number identified on their phone system. The hotel restaurant had very slow service and the food was just the typical family style restaurant stuff.
Despite all this, I would still consider coming back...just for the view. I would not stay in any of the other rooms without the waterfront view.