If you already have a flash tuner then a custom tune is the next cheapest thing to do to make power. Just ask them to get the most power they can out of it within the safety limits of the stock gear.
Funny thing is Performance Exhaust in Ringwood were exactly the same. Bunch of wankers, would never go back there. Worst part was they start the car cold then began revving the absolute sh*t out of it. Morons.