Overall, I enjoyed my visit to the Grand Canyon. This said, many irritants scattered the tour.
1. Time : Not counting the bus ride, we had about 3 hours to visit the Grand Canyon area. There were 3 spots to go to, each separated by a shuttle ride. Count approximatly 10-15 minutes to get from one point to another. You loose close to 45 minutes on the already short 3 hours you have. One of the stops is mainly to eat (loose another 20 minutes there). We ended up "running" to get a good view of each spot instead of letting the view sink into memory. Sad.
2. Bus ride : The driver was nice and good at his job ... I guess. To my opinion, he talked way too much. I would have liked more silence so I could speak with my partner on the bus. Also, many jokes were kind of out-dated. The scripts needs to be reviewed.
3. The price : It would have been ok if we had more time too appreciate the views. As it is, I dont' think it is worth the money to have so little time at each spot.
If you have a car, I recommend you drive to the same places as the tour suggests and take your time to visit.