Depends on what you mean by what is it worth... to whom?
If it is full UK spec (mine was sourced from the Netherlands) then as a trade in £12-13K, possibly £13-14K in a private sale... if it isn't full UK spec then its much more difficult... £11-12K are the likely offers at trade (possibly less) you might see up to £13K in a private sale...
Sorry for the bad news but that's the downside of buying a grey import... I've been idly looking to see if a replacement is worthwhile... so I have up to date information...