I have stayed at the Westin Peachtree hotel 10+ times in the past 6 months. I put up with it because it is cheap for a Westin and very convenient to our office in Atlanta.
The service is always very poor. I often see the same person when I check in (which is every 3 weeks or so) and they always tell me where the elevators are, etc. like I've never been there before. Noisy Ice makers are on every floor. I actually unplug them if I get a room near them. The HVAC system is bad, and the bathrooms are noisy. The breakfast buffet is pretty bad--I stick with cereal.
On the contrary, I just got back from the Westin in Toronto where they said "welcome back" when I checked in (I stayed there once over a year ago) and the whole experience was excellent. They just have better staff and computer systems.