We were two friends that used this company for a private day trip to Mutianyu.
We used a Guide named Nancy, her English is good, she is very knowledgeable about the wall and the history/different dynasties, and also she's a very nice/funny person. She arrived with a driver in a comfortable car, and picked us up at out hotel as agreed. Nancy provided us with a great day. I give her my best recommendations.
Finn.