Since the demise of my 2000 GTP 2 weeks ago, I am now in a 2006 GT. The factory stereo has the typical burnt out light problem, plus doesn't have all of the options that I loved about my aftermarket head unit that I put into the 2000 GTP a couple of months before the car was killed. I pulled out the aftermarket head unit (which looked great with the HUMount) with plans of using it for its USB, iPod, and BlueTooth capabilities.
Anyway, I haven't seen any pictures of anyone using an aftermarket head unit with their 04+ Grand Prix. I know that they are out there, but searching (here and Google) yield 97-03 Grand Prixs... Do people not swap the radios? I like the factory sound a LOT more with the 2006 than the 2000 factory head unit, but I miss the USB and Bluetooth the most.