With an XLT and Ecoboost, you can only get the 3.73 locker with a Max Tow package and that's rare.
The dealers here usually only put Max Tow on Lariats and Plats. Plus they usually only have FX4 Ecos with 3.55s. Even so, a FX4 with 3.73 is even further off being a different trim and heavier.
I previously test drove 5.0L trucks with 3.55s and 3.73s, and there was little difference in performance. The performance differences I stated between the 5.0L and Eco were very much different.
Besides, if I were to buy another truck, it would be a XLT and with that, that's the closest comparison that I can make. I'm not a fan of the Lariats leather or the FX4 boy racer look. Each to their own, as everyone has different tastes.
My 5.0L pulls my camper pretty effortlessly, so I cant think of really any gains with the Eco. BUT as I said with gears 4th and up, there's more torque so if downshifting bothers you, the Eco will do it less with these gears.
Myself, the downshifting does't bother me, but the lag off the line does. It's a matter of personal taste.
Of course, if you power braked the Eco, all that turbo lag at 1000 to 2000 rpm would be gone from a stop and it would be an animal but I drove it as I would drive it daily.
I now have a better appreciation of the Eco because I pin pointed it's positives as well as it's negatives, to explain why my previous Eco drives felt as they did.
If my truck doesn't last up to the warranty's 125,000 mile mark, I know now a bit more than I did previously to make a better truck buying decision.