I just spent two weeks in Vietnam, one in Hanoi. The motorbikes were actually something I could deal with - it was chaos, but organized. Everyone on the road seemed hyper alert and traffic just sort of flowed. The thing I could not get used to was the air quality. The AQI was easily over 120 every day I was there, and it just felt like I stuck my face in the exhaust pipe of a bus every waking moment. If Vietnam could figure out its pollution issue, I feel like it could easily be an incredible place to live.