Expensive HDMI cables are a rip-off and offer no difference in picture quality over cheap ones. So when a salesman tries to up-sell, politely tell him he's wrong and move on with the sale. Geoffrey Morrison is a writer/photographer about tech and travel for CNET, The New York Times, and other web and print publications. He's also the Editor-at-Large for The Wirecutter. He has written for Sound&Vis