Welcome! And as I have seen already, you have been into the "common problems" threads here...Yes, the G6 has some quirks that we ALL experience.
The good thing is that the MAJOR things on this car are awesome. The engine is strong and bulletproof, and the tranny is pretty tip-top too.
Steering - mainly the Intermediate shaft
Rotors - they suck, get aftermarket ones
Starting - fuel pump sometimes doesn't prime fast enough
"tire balance" - seems a few cases of pulling and vibration
Other than those, which technically, are minor but annoying, the car is rock solid.
I would agree with all of that
Debadged, Rear Window 13%, Side Windows 22% Tints, 17'' ASA AR1, Black Eyelids, Lower Grill Chrome, Injen Short Ram Intake, Under Dash/Seats Red LED's, Red and Black Seats, Alpine Head Unit, 12'' Alpine Type-R Sub, 500 Watt Alpine Amp, LED Reverse and License Plate Lights, HID's, Bug Deflector