Nightlite, I pull a 19.5ft x8ft wide Rockwood Minilite, model 2109s, dry weight 3679lbs, with everything loaded for a trip, gross weight 4239, (weight at CAT scales). Go to the towing limitations for Ford on their site, I'll try to explain. There are frontal wind resistance limitations, I believe the Ex is 40square feet exposed for the Trailer you my pull. You can determine approx by looking at exposed surface when hitched up.
Like a armchair says the WDH is very important, also the type I found out for unibody type vehicles, I went with Reese SC, Trunion type bars. I have towed all through CA this past summer, it can be very challenging on the mountains, in the TOW mode on level or rolling hills she does alright, no speed records, mountains, like the Grape Vine (into Southern CA) 3900rpms in 2nd gear, 35-40 mph, using manual shifting to give the engine a break was the only way. F150 would be better for sure in the mountains.
While there camping I ran into a gentlemen who has a 2012 XLT pulling a Palemino Trailer, 18 ft, but a great item on his roof rack, here's the link;
http://www.icondirect.com/aeroshield-wind-deflector-wd500-series/
I purchased one two weeks ago, havent gone on a trip yet, but the person states, it really helps the frontal drag a lot, his mileage at first was like the rest who pull TT, about 9-12mpg, he states the adjustable spoiler gets the wind off the TT and makes the pull much better, and he averages13-16mpg. I only have an IPad right now, my normal desktop is broke so I can't post pics, but I'll try to post some when repaired.
With all this said, the slickness of the new Ex really dumps the air right on the front of TT, so take heed on the those limitations, the lighter the better if you can! Hope all this helps, (by the way, everywhere we camp, folks always ask us, you tow that with an EX? Yes I do! Maybe better with spoiler on roof rack now! More to follow.