I've had good experiences with Circuit City. I purchased a television from them in June, and it arrived and was set up and in perfect working order within a few days. Their staff was courteous and professional. I've even seen them stay calm and polite in the glare of some customer who was ranting, using abusive language, about something (I think it was a bracket for something he purchased earlier) costing too much.
It is a discount store, so it isn't really intended to provide service as good as, say, Cambridge Soundworks or Tweeter, but for the price, they do pretty well by us.