We have just returned from the Viking Emerald - China's Cultural Delights August 2013
First and foremost, think twice before traveling to China in August. The temperatures were near 100 with 100% humidity daily. The trip has a lot of walking and stairs - the temperature makes the excursions more difficult to handle. Consider your level of fitness, if stairs leave you out of breath or walking more than 1 mile is not going to happen, consider a different trip. You will also encounter lots of pollution.
The Viking staff goes out of their way to be helpful and does a good job of taking care of you during your stay, however the trip does leave a lot to be desired. If you are paying more than their price deal you are paying too much. The ship is warm and damp - with temperatures regulated globally rather than per cabin. The dampness = a musty odor. Floors are uneven and the carpet needs to be re stretched. The cabins are a good size and comfortable.