Yes for the particular tour we managed to get, but have to be careful and watch who approaches you. Unless you're in the normal long queue. There are official guides all over the place you have to make sure when the take you to a guide/group the guide is already explaining what will happen or better still comes from behind the security barriers rather than a "random person" in a crowd. It's usually easy to spot the real guides from the touts. The coliseum tour we did was some of the ground and first floor. It was about an hour. Then the forum and palatine hill were a couple hours. They were supposed to only be 90 Mins in total. But our guides took their time and were great. You can get longer tours in the coliseum including the lower ground and upper floors, finding a quiet time is the key to less crowds and better "guide" tours. The forum and Palatine Hill were as long as you wanted after the guided part of the tour, which you probably will as there is a lot of ground to cover. Depending on how long you are in Rome use one day for reconnaissance and just watch how the things work. I think that helped us with the Coliseum choice. I hoped that isn't too much information :) Good luck