I too had them put on my F-350 last week. I haven't towed with them yet but have two trips over the next two weekends, so will report back. Solo driving, in town, I find they offer a more composed/smoother ride. DW noticed it too.
I had the OEM Michelin LTX AT/2s on the truck and set out to get the same again, but those are on the way out. My dealer said the Defender would be a better tire for my application and would be slightly better in the snow due its tread design. I usually put snow tires on my truck but don't plan to this year. He said it will certainly run quieter on the highway.