Just to update this again as I've been using the trailer for a while and I'm sure this will be a thread that comes up in a lot of forum searches.
I still, on balance, like the Nugent trailer (should say it's a utility trailer rather than a livestock trailer). However there are a few things to be aware of.
1) The ramp is chequer-plate and quite steep, and the pigs HATE it so I've used carpet tape to stick some foam squares onto it (the EVA squashy flooring stuff). It's a £20 fix but something to be aware of. The sheep bound up without a second thought, though.
2) And this is REALLY annoying- there isn't a divider gate available for the utility trailer so I'm going to have to do a home-made one.
3) The front lights stick out and can easily be knocked off by a sheep with an itchy arse if you leave it in the field
but that's just a cable tie fix as well.
It tows nice, it's sturdy and spacious, it's versatile BUT it's very annoying not being able to split the trailer.