If you really want to experience Cambodia at its very best, then I would really recommend that you use Mong Kheang who must be one of the top tour guides in Cambodia. This tour guide worked with myself prior to my trip to ensure that my tour was tailor made to what I wanted to see and not to follow the normal tourist package. He took myself to the temples when they were quiet, showed me the best places to take photographs and his knowledge was fantastic. Not only did he really looked after myself during the day but by arrangement he accompanied at night, booking pre planned restaurants and getting the best seats for local shows, he recommended local foods and dishes which I may never had tried and ensured that I was never in a position of being over charged when buying gifts/presents. In Summary if you really want to experience Cambodia then use this company, but more important make sure you specifically ask for Mong Kheang as your tour guid.