I have two. One is on the RV, and one is still in the box.
The RV one is the model that replaces the Winegard antenna but uses the Winegard mechanism. I originally bought that one because I figured it was a non-intrusive installation as it replaces the Winegard Sensar antenna, but retains the Winegard mounting tower so you don't have to replace that part.
It's a retrofit kit for a Winegard system that just upgrades the antenna.
Photo of the Jack antenna installed on a Winegard mounting base.
When I installed it, I did see some improvement. I seemed to get about 20% more stations. As well, the directional tuning does not seem as critical.
However, during long term use, it has failed for exactly the same reason the Winegard antenna failed - busted coax. The culprit is the Winegard mast as it wraps the coax around all the time, which eventually causes the coax to fail. Each time you raise or lower the antenna or rotate it, the coax is in movement.
So I have a new one in the box. I am going to replace the Winegard mast with the OEM version of the Jack (the only difference between the OEM and aftermarket versions of the Jack antenna is the mounting). The OEM base of the Jack antenna does not move the coax nearly as much. And if you ever have to replace the coax (the part in movement) it is a lot easier to do.
I bought it last year but ran out of time before I could get it installed. My difficulty is that the roof must not slope more than 3 degrees from vertical. If so, you need to add a "wedge" (that you have to make yourself), to keep the slope less than 3 deg.
If you use a slope greater than 3deg, the antenna's turning shaft protruding into the inside will be at too much of an angle to properly line up, and will result in binding. I am sure some RV manufacturers have exceeded this limit as I have seen some of these antennas at quite an angle (either that or the owners installed them that way).
But when has an improper installation that would bind the rotating mechanism stop a manufacturer/dealer/owner from attempting such an installation.
Next spring. when I have access to my wood shop again (it becomes a garage in the winter time), I plan on making a wooden wedge, then fiberglassing over it.
Jack makes an optional mounting base for the OEM style antenna to cover up all of the holes of the removed Winegard antenna base, but it does not have any slope to it.