I don't have many hotel stays compared to many posters here, but I have had such variability with Hiltons that I have not been eager to use them. (Hilton Dusseldorf was atrocious: minibar not working, they didn't bother to respond to room service calls, only parking option was expensive valet "service" despite having free on-street parking out front, etc)

This is the main reason I've stayed at Radissons is that I've never had the bad experiences that I've had with Hilton and Novotel.