China is FAR from a "police" state.
You can pretty much do anything you want as long as it is within the laws of China (which are not much different than any other country)
Jobs are what you make it, they can be fun, they can be "WORK" it also depends on the company you work for; some are ok, some are good, and then there are those that realy put a bad taste in your mouth.
Asians are not as open as Americans but getting a decent girl as a girlfriend is not difficult, just remember the culture differences and all should be well.
I have been here for almost 5 years and I have enjoyed everyday of it.
I started as a teacher and got promoted to teacher recruiter, so the possibilitie are endless.
Hope this answered your question.