If you have the worst luck in the world, this insurance policy may be worth buying. Paradoxically, if you have the worst luck in the world and buy the insurance, you will never need it and will have thrown money away for no reason. Your choice.
What on Earth kind of car takes tires that cost that much??? I choke at the thought of paying more than a hundred bucks each for tires, and also refuse to buy cheap junk. Then again, you said they are run-flats, and I would avoid those like the plague. We have had horror stories from owners of Toyota Sienna AWD owners (no spare, standard run-flats instead) and Honda Odyssey Touring owners (run-flats standard on the Touring trim level) whose tires wore out in less than 30k miles and they find out the rims rarely survive dismounting and installing a second set of tires, so they have to buy four new rims along with the new tires. Is this, perchance, how those tires cost that much?