Shenzhen or Shanghai?

Well, you can take a try in Shanghai first. As I know, the Development space is broad there.

Both of them are developed and first-elevel cities in China. There are many foreign expats in the two cities, so personally you can choose either of them. They both have many opportunities. The difference is that Shenzhen is much nearer to Hong Kong and Macau. Perhaps you love traveling and would choose Shenzhen.