Our two week trip last month was just superb. Perhaps it is not a tour for every one but for us it was interesting and fascinating in many ways. The tour was well organized and the people directing it, really were taking care of us (they even gave us a local cell phone to keep in contact). We stayed only at 4-star hotels and visit the best out-of-hotel restaurants, food was excellent, price was very very reasonable and we had no intestinal problems whatsoever (despite common apprehensions). Hanoi, Hoi Ann, Hue, Saigon and Seam Reap were all interesting in their own way, well, difficult to describe.
We have traveled through many places in the last 15 years. This is a memorable trip.
Finally, if you go ask for Ms Ruby at Asia Pioneer (make sure you go at the right season of the year)