Like Seat 2A I am a big fan of the shuttle buses. The color coding (green/white) on the schedule is not shuttle vs. camper bus, just an easier way to read the schedule.

The shuttle goes further than most tours (Eielson, mile 66 is a popular turnaround point for the shuttle bus, Tundra Tour turns around at mile 53 or 62).

I hop off and on the shuttle buses a lot. Buses stop for wildlife but usually only spend +-5 minutes at each wildlife stop. Two weeks ago I rode shuttle buses for 2 hours back and forth to get a closer look and photos of a mama bear and her three spring cubs - something you could never do on a tour bus.

You can get off and on shuttle buses if you want to go hiking.

You do need to get yourself to the WAC to pick up the shuttle buses, whereas the tour buses pick up at local hotels. Tour buses are almost always 100% full and are 98% cruisetour people.

Tour buses give some food and water on the bus. Shuttle buses have no food so you must bring all of your own food and drink (but you could eat like a king vs. the cost difference of the shuttle vs. tour bus!).

I have been in the park with a group of 9 two years ago and we all got on the same bus each day. Generally you wait no more than an hour though most times it is 30-45 minutes for a bus.

You do reserve the initial bus from the WAC but once you get off that first bus, you board others on a "space available" basis.

There are vault toilets at Toklat. Note that the prime bear viewing area is between Toklat and Eielson so you are forgoing a much greater chance of seeing bears by only going to Toklat.

I would book the shuttle bus in advance. If you try to book the day of the trip or a day before, you might get locked out. The shuttle buses can get full too.