I think it's £450. I took out a car with virtual cockpit, and to be honest the novelty wore off during the 2 hours I had the car. I can fully appreciate it in say the TT, where there is no center display, and it would have been a far better idea than the awful "iPad on the dash" approach of the new A4, but I just couldn't see myself using it.
It might help resale, but looking at the types of cars being specced on Audi-Sport.net, most people buying them seem to want a pretty basic specced manual, with privicy glass.
I ummed and aared about it for the best part of a month (with the A3 initially), but decided against it in the end.