This car has been good enough, but only because I got a good deal for it.
Had a lot of problems with coolant leaks (cheap hose clamps), the turn signal stock malfunctioned and would blind random people (cheap, poor quality part), and replaced the radio right away since the display didn't work, lots of buttons dials that won't light up (non replaceable incandescent bulbs for back lighting!!! GM your cheapness astounds me).
Its got OK acceleration otherwise performance is pretty meh. Drives like its much larger than it is, not at all nimble.
Interior is all cheap plastic, but the fabric on all the seats has held up well.
Pros: Most repairs are relatively cheap and easy (even if they are frequent). Nice smooth ride on the highway. Remote start is a fun feature. Nice big trunk. Comfortable ride.
Cons: Coolant problems, Poor quality parts, mediocre fuel economy, dead non-replaceable bulbs for many switches/buttons.
So in short, Its an OK car if you aren't freaked out by steam billowing out of the hood, or overheating in the dead of winter. If this is the car you want, get it cheap.
I bought my 2007 Grand Prix in early 2008 with around 20k miles on it. It now has 205,000 and I just took it in for my first repair - a small transmission leak that causing a slip. $300 later and it runs as good as the day I bought it. This car is a rock-solid, no-issues, dependable automobile. I drive it over 100 miles every single day and it has never let me down. I have the oil changed every 5k-6k miles and it I would drive it across the country tomorrow.
Comfortable enough for a big guy to drive.
This car feels solid and heavy - yet very responsive handling.
No room in the back seat at all.
If you're planning to carry passengers that aren't children, they will not have much room in this car.
Got mine in August 2010 with 54,000 miles on it and only paid 11000 for it with everything I could Want. Great car, I treat it terribly but have no problems with it. Averaging 18 mpg mostly a city drive for me, Not a big fan of all the exterior plastic and how the Controls are angled toward me. My by far favorite part of this car is the stiching on the leather, makes the interior shine im my opinion.
Remote Start, Sliding Sunroof, Heated Seats, The trip computer that tells me everything I'd ever want to know.