I am a mechanic in training and I am surprised by this car. I think it is a crap-shoot when getting these cars. Some of them can take a real beating mainly the 2.4L Twin cams are the most reliable. The 3100 SFI V6 aka 3.1L has poor reliability marks in all of GM's cars. The V6 has as much Horsepower as the 4 cylinder available in the car. The 2.4L can beat a lot of upgraded Civics and Focus's.
I have put 26,000 miles on this car since I bought it less than a year ago. Including 3 trips to Colorado. To be truly honest I BEAT THE HELL OUT OF THIS CAR! It takes the beatings and is ready for anything I can dish out. The reason it lasts is because of prevenative maintance.
This car is execellent off-roading and in the snow. I was told I would need a 4x4 to get to this party and my car made it just fine. I bottomed out a lot and messed up my suspension. My pal has an N-Body Malibu (Grand AM, Skylark, Malibu, Alero) which is pretty much the same car with the 3100 and his has had nothing, but problems and bad luck. He has put half the beating on his Malibu. I take out trash cans and refrigerators all the time with this car.
I Recently rear-ended my ex-gf (her fault she "brake checked" me) and totaled her car. She has a 94 Civic. Nothing, absolutely nothing happened to my car. So I am assuming Grand Ams are tough.