Interesting responses.
Jez, my car was delivered in kit form on Nov 30th 2008 so could well be part of this bad batch. Do you know what the problem was with them?
I don't believe its a split caliper so not sure that will be the cause. I had not thought of the piston seal (doh). Could be that. Either way I am talking a new caliper. At this point I refuse to be "very afraid"