Recently updated from 2003 CTS (Base) to 2007 CTS (Luxury) with 23,500 miles. 2003 was nice but the 2007 is great. After 4 years on the road car is still tight (front end, doors and windows) with no rattles or squeaks. Seats are very comfortable and performance is spectacular. Have gotten caught a couple of times jumping on a green light a little too quick. Car is Raven Black and had the stock grill painted black to match. Appearance has drawn attention. At 4700 lbs fuel economy is not bad. As some have already reported, nav system can be complicated without the manual. Waiting for one to arrive. Otherwise love driving the car and can't wait for the next one in a couple of years.
Performance, Handling, Comfort, Appearance and Sound System.
So far the only improvement would be to include cooled seats as well as heated.