I put the oils recommended by DIFFLOCK in my Disco with an R380 and it has made things a bit better when changing from first to second say. I'm not totally convinced that it's made things that much better to justify the expense.
After a 2 hour motorway run at 70 the gear changes seem a bit harsher so perhaps when they get hot they're not so great.
I would like to be able to say it's done all the things they claim but mpg just the same, still get the odd crunch into second and as I say when hot I think all gear changes are a bit harsher.
Mike