We are lovin' our Verizon aircard. It is not 100% effective but it is easy to take with you and we've had a connection almost everywhere. We also have DirecTV and have found that easy to setup.
All of the satellite internet services will tell you that you can only use the setup in a fixed position. The secret is to not tell them that you are RVers. Dusty Foot has good information on the web.
http://www.dustyfoot.com/ They have "Bird on a wire" which puts both the TV and Internet receivers on the same tripod unit.