Went on a tour with some coworkers and it was a blast. I was a little apprehensive at first given the sweltering triple digit weather, but water provided by our guides and the wind that blows in your face when you ride helps to alleviate the heat. Also, the electric motors on the bikes makes the actual biking effortless.
Our tour was led by Allison, Lexi, and Sierra; all of whom were very helpful and very knowledgeable about the surrounding area. Upon visiting the visitor center afterwords, it was apparent that our tour guides were just as well versed about the park as some of the rangers.
I would definitely recommend this tour to anyone in the Las Vegas area looking to take a break from the casinos and explore the surroundings.