Although this is generally acceptable mechanically for the car, it is important to consider the advantage of the run-flat tires. Imagine being stuck in the snow, ice and freezing cold with a flat tire trying to change to your spare tire. Another consideration is that most vehicles equipped with run-flats do not have a spare at all.
The value and performance of run-flat tires may be debatable, however the safety advantage (especially in winter conditions) is undeniable.
Run-flat tires are available for winter, too.

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