You can do around 100 miles a day on 70% and that’s more than enough for me the way I’m traveling. I have the extended capacity model. It also really depends on the route, with a lot of downhills you can probably get closer to 180 miles on 70%. On a cool night when you can just leave a window open on the trailer (so you don’t need to power it), you can get a full charge and that will get you around 200 miles a day while towing on something that has a decent amount of downhill.
I don't have a lightning but have been thinking about getting one. Thanks for the report.
One thing I thought about is that if I want to go someplace farther than 100 miles, I could just drop the trailer in a parking lot, recharge the truck at a nearby DCFC, then re-hook and be on my way. I've done this on occasion to refuel an ICE tow vehicle at a too-small gas station, and I don't see why it wouldn't work with a lightning.
So is your itinerary to go from KOA to KOA in 100 mile increments? Are there ever times when there isn't a KOA ~100 miles in the direction you want to go?