I saw a post on a charger forum that discussed a 3800 lb tow rating. But thats getting off topic from what I wanted to say to the OP.
After looking at the pic of the vertical hitch setup and thinking about it more, while it seems there might be more load on the "pin" it is probably no worse the load on the pin for my truck setup.
In fact, and not to give a false sense of security, but maybe its slightly better because you have 2 pins in reality...the one your pulling against, and the one holding the main receiver to the rest of the hitch (the one I was saying had downward pressure on it).
Anyways...interested to see how well it holds up. Travel safe. And I still recommend some sort of tow mirror.