I bought an older winegard roadtrip, the older larger one, off craigslist for $150. Installed it myself, here is my thread about the install. It was very easy.
Mine works great and I love love love it. I love being able to stop for lunch, flip the switch and in a few minutes we've got reception. Can watch the news from home while having a snack.
Plus my DirecTV DVR has hundreds of hours of TV stored on it. And it lets me watch all the recorded shows even if I'm camped under the trees where there is no reception.
The only down side is it doesn't work in the rain. If it's sprinkling it'll probably be OK but if it's honestly raining it doesn't work. And here in the Pacific North Wet it rains a lot. I tried carefully cleaning the dome and then applying rain-x, that worked for a few weeks. I haven't tried the $24 per bottle spray stuff that the RV stores sell yet. I bought a can but so far we haven't had good enough weather to apply it properly and from what I've read on the forums it doesn't work unless applied exactly according to the instructions.
If I where going to go buy one at full price I'd buy a wingard Trav'ler since weather doesn't effect them much. However they don't do in-motion.
Satellite RV - Winegard TRAV'LER Automatic Multi-Satellite HDTV Antennas