GW:
I took many a test ride from foreign to domestic, and I ended up choosing this. (New Acura's are very sharp looking as well!)
The styling of the Maliu was what caught me, lower profile, looks smaller than it really is. But the proof came in my test drive. I test drove the LTZ package, and ended up getting said package so I can not differentiate between the models. But the engine comes from the Cadillac CTS, is front wheel drive and it flies. Smooth 5 speed, with the auto shifters on the steering wheel in manual mode. (I use them when ever I am driving for fun, love the get up and go!)
Best parts: THe fit and finish is Great! I don't have a squeak, anywhere, and it is tight. It feels like an import car would. (If you go to a Chevy dealership, pop in an Impala SS or LTZ, take it for a spin and feel the interior as well as exterior fit and finish, then step in the Malibu. HUGE difference IMO!) Yes, it wasn't a plush as the CTS but it was comparable, and a bit more sporty. (Given the price difference, from CTS to Malibu I would make the same decision over. Not to mention it fit in the range I was looking at.) Otherwise mileage on hwy with the V-6 has been 27-28.6 per gallon. In city around 24-25 mpg.
Worst parts: Higher than most lip getting into car, you kind of step in over a well (best way to explain it, once you tst drive you'll see) as I am 6' 3' and I hit my foot everytime. But once in the car you will notice there is quite a bit of room, especially head and shoulder room. Also with the 18in wheels the turning radius is much larger than expected when turning a U-turn on a street, you will use the should on both sides.

Trunk is large, but the opeing is thin. Thick or wide items cause some thought as to how it will get in trunk, but once past the lip extended fromt he rear window, it is very spacious.
That is it, seats are thin and comfortable, back of front seats carved out for leg room for passengers. Carpet, interior, is the soft feel type so no hard plastic except for a couple of smaller areas.
I wouldn't second guess it, and would buy another one!
Got mine 2009 MAlibu LTZ, loaded, with 17,000 miles for $19,450. Got a steal IMO, as most where in the $23k range. So where they when they started!
Hope it helps!
dogface
For the record here is the dream car. THis is the 2010 in Velocity yellow. I prefer the Millenium Yellow on the prior cars. BUt something about a yellow corvette works for me! I would not change another car for a Corvette, Viper, Lamborghini, Ferrari, nope. And it is not a Chevy thing either, I just have always loved the Corvette!!!