Sorry to drag an old thread up, but I'm still trying to find out what happens if you do get the sub. As mentioned on the Audi A3 the sub fits into the space saver spare wheel, which is fine as Audi don't fit the spare with the polystyrene insert that holds the wheel brace, jack etc. instead, these are fitted either outside the spare wheel (on the boot floor) and the tools in a tool bag in the boot right hand side storage compartment.
Now every VW I've seen over the last few years has taken to storing all these in the polystyrene insert within the spare wheel. So the question is, if we are lucky enough to have the same sub as the Audi system, what happens to the jack and the tools ? As usual, dealer is no help what so ever.