Why anyone would go to 17" wheels and V or Z rated tires on a S70 is beyond me. I have had a S70 for 3 years now and the ride quality is stiff to say the least. In addition to a harsh ride, there is excessive roll in corners. Anything you do to make the car handle better, makes the ride unbearable. I have gone from V rated tires to H rated in size 205/60/15 and run at 30 psi and get a decent ride. I have considered IPD antisway bars and Bilstein shocks, but come to the conclusion that the ride would be way to harsh for me. I have concluded that the suspension on the Volvo is antiquated(certainly when compared to a BMW 330 or even an Audi or Saab) and that it is NOT a sport sedan. It is a great car in a lot of respects, but for best ride you have to run stock suspension with soft riding tires. In the winter, I run T rated Nokian NRWs in size 195/65/15 and the ride is not bad. It also handles pretty good. I am considering running Yokohama Avid Touring tires( a S rated tire) in the summer for better ride quality. Handling may suffer a bit, but the ride will probably be as good as it gets for a Volvo S70.