I'm very pleased with how smooth and quiet this car is. I got over 21 mpg city and 27 hwy despite miles of stop and go work zones. I think OnStar is a great feature. I love the security it gives me, and XM radio is just great. I got belted with a hard rain and no leaks and no brake fade. I feel if everyone drove an Impala, they wouldn't buy anything else .I am amazed at how quiet and smooth the motor and transmission are. You can't hear it during normal driving. I also think its the best looking car.