Does anybody have one? How do you find it? Did you fit it yourself?

I’m going to have to buy a brake controller to use with the TeaVan & this one appeals mainly because of the minimal real estate it takes up in the driving cab.

http://www.redarc.com.au/images/uplo...ion_Manual.pdf

Looking at the above link, it looks like installing & calibrating it should be a reasonably easy diy job.

I’ve only ever had small trailers with hydraulic override brakes before. None for off road use.
The Redarc stuff talks about ‘auto’ use on bitumen, & manual for off road. In particular on downhill off road sections. Can anyone explain to me the benefit of being able to apply the trailer brakes separately to the vehicle brakes in these sort of situations?