The gutter oil is a thing, but don't eat at very cheap restraunts and you'll be fine. Copycats are only a prob if you are successful enough to be copied. As a foreigner, or anyone for that matter, you are free to express your opinion until people start actually listening to it, so feel free to put Bernie sanders on your car. The censorship sucks, but you probably aren't getting tortured unless that's your thing.

Beijing is a third world city with first world aspirations. The most annoying thing about it is just propaganda and the outright lying about what the situation really is. China cares way too much about faces and Beijing has nothing going for it beyond its government top-down mandate (other cities in China are much more appropriate as tech hubs).