Ho Chi Minh is the business and cultural center of Viet Nam. It is vibrant and bustling, and is dotted with skyscrapers and luxury residential and commercial buildings, including shopping malls. The central area is still called Saigon and is in evidence by the names of many hotels and businesses. Traffic is horrendous and cars are greatly outnumbered by motor scooters, which don't always follow traffic signals and frequently turnout the sidewalks. Pedestrians need to be very cautious, but one can walk everywhere.
The French colonial influence is found here and there but is not as pervasive as the English influence in Hong Kong Part of this is due to the fact that the British influence on Hong Kong lasted much longer and was generally less brutal and viewed much more favorably by the population there.
While Ho Chi Minh is not nearly as wealthy as wealthy as Hong Kong, economic activity is clearly extremely healthy and nowhere do you see the crushing poverty visible in say, India or Bangladesh.
There are quiet areas in Hong Kong, and my hotel, Hotel des Arts Saigon, is on a relatively peaceful street in the central district. Cafes are everywhere and coffee is clearly the national beverage.