2007 Pontiac Grand Prix GXP 4dr Sedan (5.3L 8cyl 4A)
I bought a GXP used with less than 30K miles in early 2010. I now own a 2009 G8 GT, and while the performance is comparable the reliability is not. Too many issues, most being transmission related for me to recommend this to another buyer. If you have one of these and you make it to 50k miles without replacing the transmission consider yourself lucky. I began having transmission problems at 35k miles and had the tranny fluid changed but still didn't shift right. within 5k miles had to have a new tranny put in. The car never shifted right again.
The engine is awesome in these things and if mated with a better tranny would be epic. HUD is a great feature and loved the look of the red brake calipers with the drilled rotors. The leather seats with suede inserts are the best seats I've ever sat in.
The problems with this car? Reliability, reliability, reliability. Here is the list of things I had replaced within 2 years/20,000 miles of ownership (most of which were covered by the powertrain warranty or good-willed to me by the dealer, thank God). Transmission at 40K miles which still never shifted right after and began to leak fluid again at 50K miles. The alternator and battery at 45K miles. The intermediate drive shaft at 46K miles. The starter solenoid at 47K miles. There aren't too many things more nerve-wracking then worrying about your car every day. Although I never had to have the thing towed, was able to at least drive it to the dealership every time for repairs.