The question about receivers is not really in question at all. You just have to have an HD receiver to receive DTV programming in the near future (some are now reporting 2021). I suggest the H24 model or HR24 if you want a DVR. This will work today receiving only SD programming (true with any dome model antenna) and will work when the change happens someday. If/when this change happens your dome will start receiving programming in HD which will be a great improvement. What remains in question is which channels will be available since only the programming being broadcast from the 101 satellite can be picked up by a dome.
You can actually take your Genie in the RV when you travel if you like and have all your recorded programming on the road as well. You can't just bring a client as they are not receivers. You would have to add the SWM 8 hardware between the dome and the receiver but that's pretty easy and cheap.
If you plan to dump DTV and have DISH installed at home just be aware that DISH uses 2 different sets of 3 satellites to cover the US so which set you are assigned to at home can affect which dome you should buy. You will also need a wide open sky to catch all 3 satellites as they are spread across 20 degrees of sky.