At least do postdoc for two years. You got to know people and make connections. Fresh Ph. D's don't know much beyond their thesis work (well, I know you have good papers, but remember people only remember your boss's name for your work). The real growth for one's potential is in the postdoc years. If your gamble pays off, you can go to the first rate schools, right?
A second rate school is some place I advise you with caution. You need to communicate with other people and exchange ideas. In China, this kind of exchange does not happen often, except when you are in a few central cities.