Nothing.
My 2007 5-speed Cobalt is getting great gas mileage so far with at least 34 mpg around town and 38-40 mpg on the highway (going 60-65 mph). My fill-up at the pump matched the MPG on the dashboard read-out. That read-out is wonderful, by the way. It really helps me maximize gas mileage. (Our other car is a Prius which has trained me how to get everything I can out of a gallon of gas.)
The Cobalt handles great! I love the soft-ride suspension. The car handles curves extremely well. My wife and I love the ride. It handles bumps very nicely.
I've heard others complain about the seats.
I LOVE the seats. I like a firm seat, and these seats felt very comfortable when I took the car on a 150-mile drive the other day.
The stick shift is very smooth. The sound system is very good for a base model. The back seats are pretty good for a car this size. Our two kids (7 and 8) are very happy back there. The trunk is huge.
My only complaints would be the lack of an armrest - I really found myself longing for one on my longer drive. There could also be better storage areas within the car as well as larger cup-holders. The opening to the trunk is a bit small, but it handles large suitcases with no problem. Larger items would be tough to get in and out, though.
So far, I'm impressed the most with the gas mileage. On a 12-mile trip around town today, I averaged 36.2 mpg with an outside temperature of 40. I'm anxious to see what I can get out it in warmer weather.
I really think Chevy has a winner with the Cobalt. It was one of the top ten cars in sales in 2006. I see why. It's a good little car.
I'll add more comments later after I've put more miles on the car. So far, so good.
Great review, please comment again and let everybody know how your Cobalt holding up after a few more miles!
Thanks for a great review. Having owned imports and having had nothing but trouble with them, I'm now firmly in the GM camp again. GM currently builds the best cars on the planet (with the possible exception of the really awesome Ford Fusion). I'm sure you'll get hundreds of thousands of miles of great service out of this car if you want to keep it that long. I've known folks who got well over 200,000 miles out of a Cavalier, and this car is a step up from it. For half the price of a Corolla you got TWICE the car!!