After doing as much of an unbiased comparison as I could, I have decided to return the Jack antenna and keep the Winegard antenna.
The Winegard antenna I have is the Sensar III that came standard on our 2013 Eagle TT. I added the Winegard Wingman UHF Booster to it, and in effect, FWIU, now making the Sensar III equivalent to a Sensar IV. After that, I ditched the standard antenna booster in favor of the Winegard SensarPro signal strength meter and booster.
My initial comparisons in the driveway were rather inconclusive. But differences in existing weather conditions between the day I made my first comparisons and today I think made diferences between the two antennas more noticeable. After my first comparisons, I left the Jack on the antenna mast for our camping weekend. I used it with the Winegard SensarPro booster/meter since it offered more functions than the simple booster included with the Jack. But once I got out camping, the Jack antenna and SensarPro combo failed to provide a watchable signal on the two network channels closest to the campground. The signal continuously faded in & out. I swapped the antennas out and put the Winegard back up and was able to pull in the two channels with no problems. I left it there for the rest of our camping trip.
Once we got home I decided to run another comparison. I put the Jack back on the Winegard antenna mast with new coax running in the door to the Jack's signal booster and direct to the TV. I then pointed the Jack antenna in several directions and scanned for TV stations. Three stations were fading in & out and not watchable.
Next I removed the Jack's booster and connected the Winegard SensarPro booster/signal strength meter. Again I pointed the Jack in several directions, but this time I used the SensarPro to precisely aim the Jack antenna to get the strongest signal for all the detectable channels. Again the same three stations were fading in & out but not quite as bad as with the Jack's booster. I then made notes of the indicated signal strength and the direction of each channel.
Lastly, I put the Winegard Sensar III and Winegard Wingman back on the antenna mast. I pointed the Sensar III/ Wingman at each of the stations detected by the SensarPro. The Sensar III/ Wingman combination picked up every channel the Jack did, but unlike the Jack, all the stations were clear, steady and not fading in & out. The last thing I did was get signal strength readings off the SensarPro. Every one of the stations had a significantly higher strength reading than the Jack antenna did using the same indicator.
So I believe I have shown convincingly and as impartially as I could, that the Winegard Sensar III and Wingman works better than the Jack. So I have concluded the Jack can