I am a recovering Satellite Internet user. I do not recommend them for anyone who wants a serious internet connection. There are a lot of reasons why so forgive me if I miss twenty or thirty of them.
First off, in a mobile situation, you'll have to set up your dish at each and every stop. This means no internet while you're driving. I doubt you'll want to set up and tear down your dish every time you stop so there is no internet on the road at pit stops, etc.
Second, the dish needs to be aligned precisely. The movement of your bus as you walk through it or as the wind pushes on it will cause it to go out of alignment enough to lose connection. That is why you see the dishes mounted on tripods set on the ground outside the RV, with cables to trip on running inside. That is just hokey if you ask me.
Then we move on to the connection itself. Your signal gets bounced 22,000 miles up into space to the satellite, then down to your dish and to your computer. The return packet goes up the same 22,000 miles and then back down to earth again. An internet connection consists of many many small packets all going back and forth, only on satellite it's about a 100,000 mile round trip for each packet!! This causes a latency problem that would wreak total havoc on your connection. The satellite provider attempts to deal with the latency problem by manipulating your packets in some complex ways that quite often just don't work very well.
A casual user may never notice any problems with satellite internet. But a serious internet user will find themselves pulling at their hair over it's many issues.
In my opinion the best solution in todays world is wireless internet through a cell provider. If you're lucky you'll find a provider with coverage everywhere you're going to be. I know one person who has wireless internet coverage through two cell phone providers to cover his needs. While pricey, this would be a better solution than satellite in my opinion.
The benefits are many, but mostly you'll never have to lug around and aim a stupid dish. You'll be able to use the internet while you're driving. I don't recommend typing and driving at the same time but you know what I mean.
If you'd like to give satellite a try I have a hughsnet dish and a dw6000 satellite modem. It all worked just fine when I turned it off 2 years ago. I'd package it up and send it to a new owner if they paid shipping. For a mobile setup you'd need to add a tripod and some way to aim it.
-Ray