I bought a 2009 GT G8 with 110,000 miles on it. It has been a great car, the only problem I’ve had with it is that the transmission will sometimes downshift hard into 2nd gear for no reason. I find that if I release and press down the clutch quickly the issue goes away. The issue could just be in my head and the more I think about it the worse it gets. The other issue is that the car has been incredibly loud in the front end, I could wrap my finger and ear around the sound waves coming from the wheel area, it is so loud I can hear it when I talk on my phone. Not a huge deal, but it does create quite a bit of noise when driving. The previous owner had said he had them replace some parts in it at 75k miles, however there are others here on this forum reporting similar issues with their G8’s after that mileage.