Is anyone else not happy with the Goodyear tires on their XTS? To me they seem to be noisy and rough riding. I was not happy to see that Goodyear's replaced Michelin tires on Cadillac. I have only 400 miles on the car, but thinking of trading the Goodyear's for a set of Michelin Primacy MXM4. My dealer says to drive the car for 3-4000 miles to see if the ride becomes better. Has anyone noticed this on their new XTS?