Run-flat tires allow cars to continue driving after a puncture. They also remove the need for a spare, freeing up valuable space in the trunk. Sure, they’re generally only good for about 50 miles of driving at 55 mph or so, but the ability to get to a service station without pulling over to swap tires is worth its weight in gold.;There are two types of run-flats: self-supporting variants with strong sidewalls to support the weight of the car when the air leaks out, and self-sealing versions that have liquid inside to temporarily patch punctures. Not every type is suitable for every wheel, and they’re almost always more expensive than regular tires. Whether you purchase run-flats or not depends on how much you value convenience. A tire patch kit and air pump are considerably less expensive than the run-flat upcharge, but they require some elbow grease.