test report for those interested.
vw transporter 2.5 tdi lwb, fwd, lots of weight in the back
6" of snow on a graded track to get to a untreated country road that the local farmer has ploughed the worst off, but left a compacted layer that froze overnight.
chains easy to get on and off, drove slowly (2nd gear) and it was fantastic, went everywhere I tried (even a steepish hill), and I just wish I got a set years ago.
googleing around shows a specialist snowchain supplier selling what appears to be an identical set for £120 !.