Our tour guide Bobby, was fantastic, knowledgeable, friendly and gave us such interesting background on the area as well as the historical culture. He even played his flute for us in one of the back country areas.
Was originally of taking the "self guided" tour which is available. Definitely would not recommend if you want your vehicle in one piece after the tour. The back country areas are not accessible to the self guided tours, and to miss out on the information from the tour guide would be a waste.
Worth the 4-5 hour dive from Phoeniz.