I have a 96 with 170k on it. I acquired it at 150k. I have put $6k into it since the original purchased, and other than a new motor and some suspension, i am almost done modifying it. It should last another 125k before i'm through with it.
I have a different opinion about the 3800 than Stacy. I have the same engine in a 2001 Grand Prix and I have 225,000 miles on it and it's still going strong. Their worst fault is the antifreeze GM used, it eats gaskets. Other than that, it's a durable engine. Others have much higher mileage on them than mine.
If you buy another used car, you are buying an unknown. With the car you already own, you know it's history and what's already been repaired.That has it's advantages.