I've currently got a AutoGlym treatment on order for my
MCSC for about that price, but I gather thats treating the body work, interior and the roof and then provides a 10yr (IIRC) guarantee that (certain - I assume) stains can be fully removed (easily) - otherwise they'll come out and sort it for you.
I thought it was a good idea, especially as the rear seats are likely to be occupied by my two small kids at some point in the future.
SImon.,