Had a good time on this tour. While the stops between biking were informative, I would have preferred more active biking time and less chatting time. Stopping for 10 min is fine, but 20 or more is too long if it is a "bike" tour.
Believe it or not, this was a very relaxing, low stress, low energy tour. Don't be intimidated. Anyone with two legs can enjoy it. The bikes are towed up to the top of the ridge on a road with only bicycle and bus traffic allowed. You then start your leisurely ride down to the end of the road, stopping every 5 minutes or so to view a beautiful overlook and get an informative spiel from your tour guide. Its fun, its laid back and, after all the hustle and bustle of Grand Canyon Village and thousands of tourists, its a welcome break!