Some great information with using the headphones but was too busy taking great pictures to pay attention. Great to take a full ride around first and then make your stops on the second go around. With that method you'll know exactly where you'll want to stop and spend more time.
This is a typical HOHO tour. You get a good perspective of what to see in the city. However, Rome is such a crowded city the tour buses are not allowed to stay long in any particular spot. The narration does a passable job in explaining the major attractions. The tour does give you the overall perspective and could help you decide which sites to come back to and spend more time.
My biggest complaint is there are many HOHO bus tours in Rome. Signage at the stops is quite limited so it can be very easy to get confused and not know where to get back on your particular tour bus line after you hop-off. Better signage and maps would help but with so many tourist and HOHO bus tours I think the operators see no reason to invest more in signs and maps.