If you have already driven an ATV, this will not be much of a thrill or experience.
You are paying $170 to drive single file through the desert at 7 mph with frequent stops with no scenery. A friend called it “parade speed”.
Had nothing wrong with the guide, he was pleasant and thorough. You drive (slowly) out to a rock formation and drive back. There was some info about the Hoover Dam during the bus ride in, a rock discussed at the halfway point of the ATV ride, and a couple more words shared on the bus ride home.
Don’t spend your time or money.