In my experience, Vietnam is a fascinating country, if you can stand the sedate pace of life and reams of red tape (more than most South Asian countries!!)
Interesting ex-pat community....
Hanoi more cosmopolitan than HCM City.
Lovely food.
Marvellously warm people.
Go to the Co Chi tunnels and fire an AK47!
Most people stick with it for two or three years.
SHK