I commute at night, when there's less traffic in Southern California. The stretch of hwy 101 I cover always seems to be under construction with lots of road hazards. To avoid getting stranded, I mounted run flats on my S's 19" wheels. The new generation of run flats are much better; not loud or harsh. I replaced the Goodyear Eagles with Bridgestone Potenza RE960AS Pole Position RFT 245/45RF-19. (Filled w/ nitrogen) They are very close in spec to the Goodyears. Same 1,653 lb load rating. A little better grip, AAA vs. AA. And a little faster speed rating V vs. W. They are 1/2" wider and a bit heavier (6 lbs/ea). So far I'm really liking them, and the V tread pattern looks kind of cool. I also carry the Tesla air pump w/ tire slime. At o-dark hundred, if I get a flat, I'm hoping to limp to my destination rather than be flatbeded to a closed tire shop or service center. At least that's my plan. I'm not sure why Elon & Co decided not to go with run flats on a car with no spare, but if I had to guess, it was because they didn't want the extra weight (24 lbs in total) and slightly diminished range. I don't think ride or handling were the issues. Having driven an 85 mile range Nissan Leaf for the last 21 months, the Tesla with 250 miles, has made my range anxiety suddenly nowhere to be found.