WOW! I replaced the Bridgestons RF (run flat) tires, with Michelin Pilot Sport ASXL. The ride with the sports suspension, improved significantly, and eliminated the jolting, without compromising the handling. As a bonus, it may enable me to use the car year around in Upstate NY, without having to invest in snow tires, and if I can get even close to the projected 40K miles tread life, I will be even happier.
Engine and brakes.
Give the customer the option of selecting an all season, non RF tire, which will be less expensive to replace, will ride, better, last longer, and my negate the need for snow tires in the cold climates.