We took this tour last year. As I recall there were five days (maybe six) on which we spent in excess of five hours on the bus. But the average of all the other days was probably about four hours per day on the bus. So, yes, I would call the tour "bus intensive". The bus we had was quite comfortable and rest stops were frequent and typically interesting. On average the rest stops happened about every hour and a half and each stop was about half an hour. Others may have a better memory for details, but that's the way I recall it.