I have a friend who has one of these carts, but I never took a really close look.
I'm sure I don't really need to remind any of the people on this list, but just in case, driving requires careful preparation and the potential for injury to you and your pony is probably greater than in riding. I have friends, two very experienced horsewomen, who had a serious carting accident with a Fjiord pony during a driving clinic. This was not a green pony, but he freaked and wrecked the cart and scared the spectators to death. Nancy