I went for a 2 day tour to Hamburger Hill, Khe Sanh and the DMZ area including the Vinh Moc tunnels, I was interested in learning as much as I could about the war, let me tell you, Mr. Vu has an unbelievable amount of knowledge on this area and the Vietnam/American war in general. It was a fascinating tour, and was brought to life even more with accompanying photographs that M.r Vu brought along to show you what the geography looked like during the war. 
Both Mr Vu and the excellent driver Mr Quy made the tour very enjoyable and I would highly recommend to anyone. Best thing I did in Vietnam. 
Carlo