I was in Vung Tau for the weekend in August 2010 on pleasure with a friend. The Petro House was an older hotel and while it wasn't 4 star hotel when compared to 4 start hotels in the United States it was easily a high 3 or 4 star hotel when compared to similar countries. The rooms come equipped with complimentary web access, bottled water, HBO and other movie channels and a menu-based breakfast is included. The hotel's staff is helpful and while they don't speak very much English, they are more than willing to suggest good seafood restaurants, flag down cabs and exchange currency. The hotel additionally has great restaurant where you can eat breakfast lunch and dinner. Also, while the hotel doesn't have room service any meal you order at the restaurant can be brought to your room and while they don't have a swimming pool, they have a partnership with the Rex hotel which does have a pool.
As far as the neighborhood, the hotel is only a ten minute taxi ride from the main port where the Petro Express ferry and other ferries drop you off which is really convenient. In general the hotel is in a great neighborhood which is pretty close to some great stores, restaurants and clubs. It isn't in the tourist district, so you will get the more authentic Vung Tau experience. And the hotel itself is mostly stayed at by people in the city for pertroleum related business.