After trying a few workshops around town, I can highly recommend Prestige and Performance over at Coorparoo for servicing and performance work. Mike, the owner has been great.. he's fitted my suspension parts, oil services, diagnosed electronics, wheel alignments, etc and the prices have been good. I've also found he treats the cars like his own.
I booked our 2 cars in for servicing and let's just say the dealerships would have charged more for parts alone!
Previously, I used to go to the large workshop at Milton that park the ferrari's out the front and had nothing but problems and expensive bills...anything performance related and they didn't want to know me. They even damaged a rim on my old car and told me it was the wheels' fault.
