There is a bit of a thread on AULRO on these, Dave Ashcroft (Ashcroft Transmissions) stocked them for a short period, then stopped. His explanation:
Hi Rick, When we first tested the Kaiser diff on our 90 I was impressed, our demo 90 is an auto puma, it drove well and just gave a very small clonk occasionally but this was far better than the Detroit locker so we bought some,
Having sold some and got feedback from customers I have since leant that they behave quite differently on a manual disco or 90 and can make a repeated clonk quite badly when you are off the throttle and on full lock, ie turning into a parking space,
This combined with the fact that they were quite expensive especially when compared to our air locker which was launched around the same time meant that they have not sold very well so when our stock ran out I decided not to reorder,
They may be better on a 110 due to the increased wheelbase but the Detroit was not a problem on the 110 and the Salisbury Detroit's are far cheaper, Pls feel free to post this reply on the forum,
I have no experience of these myself so cant comment.
I have front and rear ARBs in my 90 and am currently looking at what to put in the rover front and 2 salisbury rears on my 6x6.