FREDERICK, MARYLAND -- I had recently purchased a 55" Vizio HD TV from Costco and my friend alerted me that it had gone on sale. That same day, I took my receipt to customer service and spoke with the manager. After confirming the price change with an associate from that department, the manager promptly refunded the difference to my credit card. No hassle, very easy.
A few weeks later, I purchased a PS3 bundle, but also received a new one for my birthday. I had played it once, but having another one given to me, I took the one I paid for back to Costco for a refund. When I took it back, they had an associate from that department check the system and made sure that everything was in the box. After that, a full refund. Again, no hassle.
With this type of refund policy and free, extended warranties on big ticket electronics, I don't know why you would purchase these things anywhere else! Good prices & great customer service. I have bought 3 HD TVs from Costco this year alone and will continue shopping at Costco. I have yet to see better deals on what I have bought.