Hi,
I have one in my car and I have never actually seen another one in a car. Andy Wiltshire had one for a while and I saw some photos of it, that is as close as I have come to seeing another one.
Mine was leaking so has been out and back to Arch for repairs and we understand from Bruce that he only made about 25 or so and there are two different types. I have the smaller one which has a capacity of circa 45l, the larger one is probably about 55l.
If you want to know any more send me a BM
ALAN