There are 3 answers to your question. Not all are YES, (No and perhaps)
First: NETWORK television (ABC, NBC, et-al) are spot beamed for most of the country, If you drive more than a couple hundred miles (Sometimes less) you will be "in the dark" as far as those stations are concerned.. There are ways around it but.. Frankly they are cheats.
There is one legal way around it (Posted at end of this post)
Next: The tailgator works well with a SINGLE DISHNETWORK receiver, specifically the VIP-211.. It will not work with DirecTV or other Dish receivers.
NO DOME works well with multiple Dishreceivers.. (THough you can have multiple domes)
DirecTV (non-hd) likely will not include network TV period, but it does work well with a dome, Both single and multipe receiver installs. Provided the dome is a "Dual" (Means 2 outputs, NOT two LNG's Two LNB's is a "Twin" and always a dual).
HOWEVER NO DOME will do DirecHDTV.
Dish type antennas, need to be aimed (Though you can get an automatic roof mount antenna, you park, level, press a button and assuming you are NOT parked under the evil signal eating tree, or in the "Shadow" of somethign, it locks on the birds and you get TV). Ground mount antennas you will have to aim yourself).
Dish type antennas work, period, you get the antenna that matches your service and they work.
NOTE: If you put a roof mount on be sure to install an A/B switch in the LNB lead and carry a tripod mount (Ground mount) as .. Well, see signal eating tree.
A-Rooftop A-bove, B-ground Block in Basement or a Bulkhead (Through wall) or in my case it's a ground Block on the Brake Bell crank Bracket (you get the idea) down B-elow.
Now: how to get network tv nationwide when traveling and not "Cheat".
You get an RV account, Install it in the RV, be sure to get your full compliment of 4 receivers.. Put 2 in the RV,, 2 in the house (you will need to buy a dish off E-bay or Craig's list and aim it yourself, ONE TIME, not that hard to do) This qualifies you for "Distant Network Service" (DNS) for a small fee, you get, depending on the service, Network stations in LA or NYC area or some other citeis and possibly more than one city.