Just wrapped up a quick stay here, nice to see this place hasn't been spoiled by the Marriott cost-cutting squad yet! Great welcome, great service, great room.
Platinum breakfast benefit is I think still a $14 voucher per person, which as a small criticism is starting to get a bit low given I think the menu prices have gone up slightly with inflation since I last stayed here! I stayed on a Luxury Privileges rate which included breakfast and it was the same voucher I was given for that (chose points as my Welcome Amenity, not sure if I could have had double the amount to spend at breakfast otherwise!). I do generally prefer a high quality a la carte menu to a breakfast buffet, so I'm happy with the breakfast set up.
Booked a Grand Deluxe Landmark room and was upgraded to a large suite with a large terrace (I think it was a Superior Suite with Terrace). Bottle of wine and cheese board waiting in the room as a welcome amenity. Location is great.
Overall, I struggle to see why you would stay anywhere else in Chicago if you are loyal to Marriott, unless you were will to pay nearly twice the price per night for the RC.