Great location but hotel needs an update.
Older hotel that needs an update
My husband and I were in Chicago for a wedding. We stayed at the Marriot because we were able to get a reduced rate because the wedding party booked many rooms. The first room that we were shown was very large, with a couch, chair, microwave, refrigerator, large bathroom etc. but the air conditioner was very loud. We were shown to another room which was okay...no couch, microwave, refrigerator etc and we foolishly took the room instead of asking for the larger room. This room was rather on the smallish side but near the elevators which was good. However, the room was very, very noisy...not sure why....it sounded like motors that kept going on and off. Even though we were on the 30th floor, you could hear the traffic, the ambulances, the police cars etc. Again, we foolishly did not ask for a better room...My husband said because it is an older hotel, the insulation is not as good as the newer hotels. We had lunch twice in the resturant and the food was good, but depended on what you ordered. The sandwich/soup special the first day was excellent, tuna sandwich and soup but the second time the sandwich was roast beef which was overdone and tasteless. Surprisingly the prices were modest for a city hotel restaurant and the ambience was lovely. 
Hotel elevators were fast and even though the hotel was very crowded they came pretty quickly. Towels were on thin side, not thick like the newer ones. Soap supply was meager. Again, I should have called for more but we were so busy with the wedding parties that we didn't have time to call. 
We did share our concerns with the hotel personnel and they gave us some extra points on our Marriott card which was fair. As I said, my mistake was not complaining and asking for a room change.
There is a Starbuck's in the hotel which is convenient and a Cosi restaurant across the street for a quick breakfast, lunch or snack., but way too many carb items....they need more healthy choices.
The location of the hotel is great...next door is a Norstrom's and of course being on the Magnificent Mile was a shopper's paradise. We could even walk to Millenium Park which is a beautiful park with two great sculptures and convenient to the Art Museum which is a must see. I did an amazing amount of walking each day to really enjoy the city sights. 
Would I stay there again? For the price that we were quoted it was a great deal but if I had to pay the regular price, I don't think so. 
My sister in law stayed at the hotel and she was charged more for her room than we were. Not sure why. It is possible that she did not book using the bride and groom's names. But she said she would look into to. It is amusing that they were shown the first room that we were shown and of course, the air conditioner was still making the awful sound. They sent someone up to fix it but he couldn't. It is strange that they hotel management would show the room again, without fixing the racket.
All is all, we had a fabulous weekend and can't wait to go back to Chicago...I love NYC but Chicago has the culture, the friendliness, the shopping, the restaurants like NYC but so much cleaner and newer. And the architecture is amazing!