This property is rough around the edges
Staffed by a lovely bunch of folks, the Sheraton Chicago Hotel and Towers is coming apart at the seams. The yet to be completed renovations cannot be finished soon enough.
If you're sensitive to mold, then do yourself a favour and check your bathroom carefully for mold upon entering your guestroom for the first time. The first guestroom that I was put in had a bad black mold problem in addition to it being in a state of disrepair. The guestroom to which I was subsequently moved also had a mold issue and was similarly less than ideal, but I was too busy to move again. I did let a woman on the reception desk know about the second mold problem upon check out, however. It seems likely that renovated guestrooms are handed out only by special request and even then they are necessarily subject to availability unless you've got some kind of status with Sheraton or you've paid a top rate. Both of the rooms that I saw were dated and a bit tatty.
Cleanliness also seems to be a problem. I found a few glaring cleanliness issues during my stay at the hotel, but I discussed only three of them with hotel associates. How hair finds itself smeared on to a bathroom ceiling is beyond me! It could have gotten there by the hand of a guest as easily as it did a dirty housekeeping or maintenance rag, but the point is that it shouldn't be on the ceiling at all. 
Look, I know that it has to be very difficult to keep guestrooms clean and I take care to leave a couple of bucks for housekeeping cleaners every day, but hair on the ceiling? In my many decades of travelling, that's a first for me. It was a bit of a shock in a hotel of this calibre.
If you'll be driving a great deal while in Chicago, then please do know that as of the date of this review and unless otherwise indicated on the meter pay station or by signs posted in the neighbourhood, you can park on the street for free around the hotel from 9:00 p.m. at night until 8:00 a.m. the following morning. For those arriving late and leaving early throughout their stay, this can amount to a significant savings. Empty your car of any valuables and provided it isn't a fancier late model vehicle, it should be safe enough on the streets of Streeterville over night. Street parking is available on the ramp descending from reception or on the streets below the elevated reception level of the hotel, which streets can be accessed from the reception level by a set of stairs at the end of East North Water Street. Parking in this manner saved me anywhere from $60 to $110 during my stay.