I've been coming to Vietnam Palace once a week for four years now. I've seen it transition from a fairly shady-looking place to a lovely, classy restaurant. One thing hasn't changed with the updated decor: the quality of the food. Ever since the first time I've set food in this place, the service has been impeccable and friendly (keep in mind it -does- get busy on weekend evenings; the staff still do their best to get the meal on the table within 15 minutes), not to mention fast. The food is authentic, home-style Vietnamese; try the deluxe Pho, the bo luc lac, the salt-battered seafood, the fresh beef marinated in lime juice, and the roast pork with wonton soup.
What else is amazing, aside from the consistently great service and food? The prices. Most entrees are around $10--incredible considering how tasty, fresh, and large the portions are--and appetizers, salads, and desserts are all within a $5 range. Drinks from the bar are pricier, but stick with the tea; it won't detract from the authentic dining experience.
The best time to go if you want a quiet meal with someone is on a weekday afternoon, after the lunch rush; usually there will be a family or two and other than that, you'll have the place--and the friendly waiter--all to yourself. Give it a try if you've never had Vietnamese; the staff are happy to recommend something for every palette.