Thanks for your comments All!
I have asked for a full report from the dealer as to what work/investigation was carried out on the car in the week they had it, as nothing has changed - this seems to be proving difficult for them as they havent managed to come up with anything in over a week, not even managing to return my calls..

It totally amazes me how a reputable dealer can be so arrogant about the whole thing!!

I am now waiting a response from Subaru Australia...