I just helped my neighbor get his Winegard Carryout and DirecTV DVR installed yesterday. For DirecTV, the Carryout only sees satellite 101. This is the satellite that carries only SD programming. There is no HD with a DirecTV/Carryout combination.
The two RF feeds off of the Carryout can supply a dual tuner DVR or two normal receivers. The DVR tuners both see a signal and you *CAN* record two programs at one time. The concern about having to watch one satellite at a time is a Dish issue. DirecTV only needs one satellite (101) for SD programming. In some markets (usually smaller ones), the "local" channels are delivered on a different satellite (usually 119). The Carryout doesn't see 119 (or any of the other DirecTV satellites - 99, 103, 110) so you won't get "locals" if you are in one of those unlucky areas.
Update: The Carryout will switch to satellite 119 if the tuner on the primary RF feed requests it. Then any other tuner(s) must also view a channel carried on 119. So if your "locals" are on 119 you can see them assuming you are within the coverage of the spot beam. There doesn't appear to be much SD programming on 119 so hopefully the Carryout will not have to move for you. It is amazing what you find when you read the manual.
I haven't tried it with a Carryout, but I have supplied a signal to a dual tuner DVR and a standard receiver at the same time from an 18" antenna. The 18" antenna had two RF feeds just like the Carryout. Running the two wires from the antenna into a 2x4 Winegard splitter provides four useable outputs. The only problem is getting all that wiring to the various receivers. But once you get over drilling holes in the side of your Montana, it is pretty easy. I am confident you can feed multiple receivers/tuners with the Carryout.
Be aware that the newer DirecTV receivers require SWM technology and will not work with the Carryout without buying some additional pieces parts.
The Carryout is a good solution for DirecTV users *IF* you can live with SD programming.