You'll be blinding (glare) oncoming drivers, depends on the state law and you may get tickets. You are better off go aftermarket LED headlamp unit replacments.
Tow tune is horrible on mpg, I got like 21 mpg for daily driving and not recommended.
Depends on the load, road grade and your lead foot, truck can go into electric mode just about any speed. I went into electric mode around 70 mph on highway, downhill, on right lane and no one behind me.