Does anyone have any experience of using a 3.5 tonne box for a big horse? Like a sort of 17-17.2hh middleweight type? A friend of mine is looking at options for boxes and likes the look of mine but is bothered about size and weight etc. I've only ever travelled up to 15.3 in mine and that's about the limit, but mine is a van conversion, not a box type body. Would the bigger versions be a sensible option, given they will only be travelling a single horse, especially as the bigger versions have reduced payloads?