Stayed here over the weekend. Nice hotel, great location from a tourism perspective. Hotel breakfast is just an omelette station and a couple of bread options. No issues with service and the hotel is brand new, so of course all is very nice.
I was told that as a Diamond I could go up to the rooftop and tell them I was a Diamond guest and that would get me in. I only went up one afternoon, and had no problem walking in without any questions about who I was. While it is nice, it's not necessarily a reason to pick this hotel over any other options. The drinks/food are overpriced, which was to be expected, but there are many other places in Chicago with rooftops and great atmospheres.