OK hotel, nothing extraordinary
We stayed there for 1 night in June. 
Two positive things: view over Lake Michigan is really awesome and the Whiskey Bar on 31-st floor (though a bit overcrowded and loud)
Nothing specifically negative; just standard hotel like many others. Rooms are rather small, but clean; beds are comfortable. 
 Location is really great. But I think that city like Chicago could have something more spectacular in such prime location.