The best way to describe the ecoboost is like having a .22 caliber revolver that can also shoot a .44 mag round. The 5.0 would be a 357 magnum i guess.

My situation is the complete opposite of yours conger. I have a young family with my first kid on the way. I opted for the 3.5 ecoboost 4x4 long bed with 3.55 gears to tow my 27" toy hauler.

If I were in your shoes I would get an ecoboost with a taller gear ratio like the 3.31s so you get the best fuel economy. I think the ecoboost is more fun to drive. The only thing I miss is the classic v8 rumble.

My 2011 ecoboost averages between 19.5 and 20mpg right now. It's most happy at 55mph on flat ground. At 75mph on the highway my average drops to 18.5mpg.