My 2005 Cadillac STS rides like a dream! It is tight, smooth and quiet. Its standard features were enough, but with just the V6 Luxury Equipment Group and Premium Upgrade Package, I have more creature comforts than I have ever had! There has been no wind noise and it handles the bumps as well as any foreign luxury car. I look forward to the ride to and from work!
My favorite feature has been XM satellite radio. However, the keyless start is quite nice also.