We were for about 3 weeks in Angkor Wat and Vietnam in 2005. We arrived in Ho Chi Minh City and went over to Angkor Wat after two days. Three days there are sufficent; I (as a man) did not get bored at all. We then had still more than two weeks went to Hanoi, Sappa, Halong Bay, and the usual North-South tour back to Ho Chi Minh City - wonderful trip; highly recommended.