Presently and pleasently working my way though a dozen pirramimma maclaren vale cab savs,It depends on what you want.
For me:
Barossa for shiraz and riesling
Margs for cab sauv and chardonnay
Victoria and Tassie for Pinot
But bringing it back to the original point, if you're going to a wine region for a holiday, I'd prefer Margs over Barossa for everything else it has.