should probably also clarify that the 3500kg limit on that type of trailer applies in the UK. Some other countries allow higher loads to be towed, vehicle allowing of course. I think america is one and their hitches will be beefier than ours and their cars are often big 5 litre V8s on a huge chassis. A lot also have electric actuated brakes instead of over run type and anyone towing large loads regularly over there will probably be equipped as such, the rental trailers like U haul might still be over run brakes. From what I have seen the USA is much better in terms of towing, larger loads and safer systems. We are stuck in the dark ages and I do agree with the new rules as much a PITA it is, I just wish it was easier and cheaper to get your test done.