There are two companies, for TV and also two for internet. Since this is an RV forum, I would assume that you mean for the RV, and probably for TV? Either company will work just fine for TV. You have several choices of dish, depending upon what you wish to spend. For the low price, you get the dish exactly like on your house, but mounted on a tripod. It takes some time to set up and there is a learning curve for getting it into service. The next step up is the crank up dish on the top of the RV. It is less difficult to aim and it just cranks up, and is ready to go. But it will cost more. Next step up is the automatic dish. With it, you park, turn on the dish and it finds the satellite and you are ready for TV. The highest cost is the "in motion" dish that is mounted under a dome and that will track the satellite as you travel so that your passengers can watch TV as you drive. All of those choices are available for use with either Direct TV or with Dish Net. It just depends upon what you are willing to spend.
There is a down side to any of the roof mounted dish systems. That is the fact that heavy timber will interupt the signal and you won't be able to get TV. With any of those you either do not park under thick shade trees, or you adjust the RV's position to where there is an opening in the trees. With the cheap tripod mount dish, you get 100' of coaxial cable and you can position the dish to get out from under the trees.