I stayed in both hotels but I think Hilton Beijing is much better than Hilton Shanghai in terms of quality service. I once had to wait nearly 5 minutes at the breakfast cafeteria where there was just two waitress serving in the rush hour. I didn't encounter such problem in Hilton Beijing. And by the way, the breakfast buffet (which is free for Gold and Platinum) in Hilton Beijing is one of the best of Hilton chain.