I have the 10spd behind the 3.5 EcoBoost ('20 Expy--which is a lot lighter--also has sport, eco, tow, etc. it does not have a 'start in 2nd gear mode for sluper slow rolling which ECO mode should do).
It is not brilliant, and IMHO needs a small software fix to really get sorted because it is a little bit confused some times and sometimes feels 'draggy' (and it is not the brakes). I like the economy and acceleration but on a scale of 1-10 I give it an 8. If they had an 8-speed that was "brilliant" I'd take it over the 10 spd, or if I had my druthers I'd want the 10-spd packing 4.11s+ (3.73s now) to justify it a bit more.
Either way, there is room for improvement.