F150 w/ 3.5L POWERboost towing experiences?

I think you're jumping the gun here. You're talking about a brand new powertrain here, in a year where production has been delayed. Have any of these even hit dealer lots yet? On top of that you're asking in the middle of winter, far from prime camping season.

Though if I were to speculate, it's a 3.5L Ecoboost engine coupled to an electric motor. I can't believe it's anything but better than a straight Ecoboost as long as the battery holds out.