My flatscreen got a crack in it and HP sent me a new one the next day. I worked on a faulty Dell computer at work for years because they don't seem to have customer service. I have not used HP's tech support because I have my own personal tech guy who charges me nothing and speaks english without an accent but I'm sure it's better than Dell's.
Well, I have never owned a dell, but, I have only owned hp. HP's are of great quality,(so you are thinking: "what the hell is my point?") however, you have to speak freaken arabic to understand their customer service. That is a big negative, big enough to give em' the thumbs down.
Both companies tend to make some pretty low quality stuff but I definitely prefer HP to Dell. I have a nice HP laptop and it is better built than the Dell laptops I've seen, aside from the xps series.