Well, I finally got around to spraying the interior of my car with Autoglym Lifeshine of the week-end. Apart from the noxious fumes it was a very easy task to do. Where the spray has contact the interior trim it left a fine white powder, which was easily wiped clean. I guess only time will tell if my money was well spent. But £30 for the kit still seems like better value than £300 for Audi to do this for me using Supaguard. All I need now is a dry week-end and I can apply the gloss protector.....this Indian summer is looking less likely I'd say 
2004 1.4 TDi (90) SE, Cobalt Blue, Climate control, Cruise control, DIS, Sport seats, Winter pack, Symphony II.
2004 1.4 TDi (90) SE, Cobalt Blue, Climate control, Cruise control, DIS, Sport seats, Winter pack, Symphony II.