The winegard systems are the standard for which others are judged. Actually there is only one competitor.
The domes are great systems. The only limitations they have compared to a standard or automatic full size dish is 1) when the get wet they can loose signal because of the film of water on the dome 2) they are typically a very narrow dish to keep a low profile, which can make it harder to get a signal sometimes, 3) they typically can only see one satellite at a time, so if you are using more than one receiver they can see different channels but have to be on the same satellite.
We had the Winegard Roadtrip SD dome and it was great above those limitations listed above.