Never had anything remotely look like violence, robbery or even weirdos like that in Shanghai/Suzhou.
The time before this US thing (where nothing happened but it made the hairs on my neck stand up and we did realize we were close to getting robbed) was about 10 years ago when I got robbed at knife point in a small town under Barcelona. While feeling completely fine walking through weird neighborhoods in Belize. So you never know...
When I was around 8 my teacher in school said 'if you go to Amsterdam, you die; this city is so dangerous that when you go there, you will most surely get robbed, raped and murdered'. Apparently in a certain part of the Netherlands this idea was prevalent as when, 10 odd years later, I went to the university of Amsterdam my grandparents had something like 'Ok, this is it, this is the last time we saw him. He dead.'. Then I lived there and I actually lived in the neighborhood which was 'known' to 'everyone' that you will die there; de Bijlmer. Ofcourse, it was great; all these murderers and thieves offered me beer and food before going to uni in the morning; they invited me to the bars under the flats at night. I walked through that place (and other 'you'll die' places) in the middle of night and never felt anything resembling fear.
I want to go to Brazil and I will because of a client soon, but he, born and raised in Sao Paulo, says even he doesn't like it because of the crime. And he knows this city well. I'm not sure what to believe but we'll see... Not bringing any iPhone that's for sure.
