I too am a bit skeptical. I am going to give a try at some point and see how it goes. Discover has a .pdf file on their website with instructions in Chinese to carry with your card to show to the cashier explaining relationship. Here is a link to a msn article telling about the agreement between the two and it is saying they are supposed to be accepted system wide on each others systems...

http://news.moneycentral.msn.com/pro...108&id=6181210