I've only stayed in two Rens, but I've liked them both.
The Schaumberg IL Renaissance is one of the finest hotels I've ever stayed in. Huge picture window, Flat screen HDTV, a hotel with considered architecture and STYLE. The CL seemed fine to me. Ate my oatmeal reading the Wall Street Journal and overlooking the flatlands. At night, enjoyed a fine cup of "Mighty Tea" and spoke with some fellow travelers.
The TV built into the bathroom mirror was an irritating novelty. Finally figured out how to turn it off...
In a few weeks, I'll be checking out the Kuala Lumpur Renaissance. Any tips?