We have a dome dish on our motorhome, and have Direct TV at our home. All we have to do is take one of our receivers with us in the motorhome. On the back of the receiver you have a choice of Channel 3 0r 4. Just be sure to tune the tv to which ever channel you choose on the Direct TV receiver. We have never had a reception problem. The nice thing about the dome is it automatically searches for the satellites and locks on to them.
When we had the travel trailer, we had a portable dish that we mounted on a post attached to the ladder. The aggravation was getting it aimed properly at the satellites. Using a satellite finder made it a lot easier, but at times it was a pain.
One advantage of the portable vs dome is you have some flexibility getting the dish around trees. With the dome, if there are trees between you and the satellites, you are out of luck and stuck with the regular antenna.