There were a few reports either here or on another thread, but I didn't remember seeing any details about transactions. Rest assured it's a legitimate UnionPay network card, and you won't experience any issues you might have with a Discover card in Mainland China. As a bonus, it works in other UnionPay locations whereas Discover only works over the UnionPay network in Mainland China. Since getting the card, I only did a single test transaction in Hong Kong, but the transaction processed over the UnionPay network without any difficulties. You can see my post here.