Logistics are problematic. They did not stop where they should have to pick us up on day one. I called the booking company who called the bus company who said "?" and assured us they would be there with the next bus in 30 minutes, which they were but it was a bit stressful waiting in the rain for them.
It would seem that a bit of technology could help them. One person on the bus is in touch with the office via a radio. I would think they could track the busses with gps and that they could scan passengers on and off and track bookings, etc. on an ipad or something. They could post target and even updated schedules online so folks would not have to just wait at the stop for 20 - 30 minutes or phone in for estimates.
That being said, your experience will depend largely on your guide. On Day 1, we had a great guide who comfortably narrated the entire tour. On Day 2 we got on and off several times and the two guides we encountered were less than stellar but we already had the info we needed to plan where we were going.
After the initial hassle, this worked well for us since it was two rainy/windy days and we didn't want to get totally soaked while out and aboot.