Ron,
My TV and the Trailer Life test vehicle are 2014 Jeep Grand Cherokees, 3L diesel engine, 9-spd tranny.
Yes, going from 28 mpg to 14.5 mpg is a big drop, but it is still better than most pickups. Plus, as a daily-driver, the 28 (I get over 30 on many extended trips) is a pretty livable number.
I have no complaint about setup, as it takes a couple of minutes. All trailers have to level and extend stabilizers. Once that is done, it is really 2 or 3 minutes to set up. I have done it in the dark, and it is still simple. If you have two people, it can be done in less than a minute.
I like it because we go to remote sites, and often there are trees leaning over the road. If my Jeep fits under, the trailer will. We have been in many places a full-height trailer would not make it, due to the trees along/over the road.