Hi Malc,
I had a thread on it on another site, but the gist of it is that the car had a load of faults (some dangerous) and had to be assessed by VOSA who I think took action against the issuing MOT place, but not the dealer: Advice on used car bought from dealer - Page 1 - Car Buying - PistonHeads UK
I actually had the corrosion cut-out and remedied, put new discs and pads all 'round, along with new tyres, hub and a caliper, so I can use the car now, but my wife doesn't trust it and won't really drive it. It still has a few issues like needing an air con compressor, leaking radiator and occasional VCS light.