In my preliminary research of the 2016 S 550, I surprisingly found that the car doesnt come with a spare tire. But rather has run flats as standard equipment. My question is whether you can just swap out the run flats for conventional tires. And, if so, is there a spare and jack kit that can be purchased that will fit this car. I just really wouldnt feel comfortable taking a long trip without the benefit of having a spare in the trunk. I would appreciate any feedback anyone an provide on this subject. .