I haven't stayed at the Westin, but it is slightly out of the mix of things. I have stayed at the Sheraton Centre numerous times during the last year. It tends to be really busy, but the staff is always really helpful. However, over the 10 or more times I have stayed there I have had the elevators out for over 4 hours, at least 2 fire alarms in the middle of the night, and dog excrement in the hall (thank god I had my glasses on and didn't take a bad step
). A colleague of mine also had another guest given her room key late at night. Luckily my colleague had the safety lock on and the other person couldn't get in. For each of the incidents, the hotel has honored the Sheraton promise and provided extra points for the inconveniences. My colleague ended up getting 20k points (!!!!) for her incident largely due to the other guest complaining about the inconvenience caused to her and my friend.
I think because of the size of the hotel, these things are fairly common there. Nothing was so awful for me personally to stop staying there due to the convenience of the hotel being so central. I started to get used to it and all the extra points I got definitely helped the situation. In addition, the view from the lounge is great!