DBest

I have a 2007 IS350 with 18" rims, live and drive in a city with rough roads and the ride quality is rattling me to bits. I'm considering dropping down to 17" rims to get a taller and more (hopefully) more supple tire. I'm willing to give up cornering performance for ride quality. How much of a difference would I notice by changing the wheels to 17" versus current 18" (excluding any differences in swapping out the tires to a different brand/model)? Thanks.