Deciding on my next trip...
My favorite guide was the National Geographic Traveler. It had the best information about the country and the best photos. It did a really good job of getting me excited about experiencing Vietnam.
If you want really specific information (eg. hotels, train stations to get around, etc.) than Foder's is the way to go.
The New Mexico and Bali book was really hard to get through in terms of how they organized the information. Plus the photos and the font seemed really small...